&EFA
United States
Environmental Protection
Agency
Office of Air Quality
Planning and Standards
Research Triangle Park NC 27711
EPA-450/3-87-025
November 1987
Air
Residential
Wood Heaters
Background
Information for
Promulgated
Standards
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EPA-450/3-87-025
Residential Wood Heaters —
Background Information for
Promulgated Standards
Emissions Standards Division
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air and Radiation
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711
November 1987
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This report has been reviewed by the Emission Standards Division of the Office of Air Quality Planning and
Standards, EPA, and approved for publication. Mention of trade names or commercial products is not intended
to constitute endorsement or recommendation for use. Copies of this report are available through the Library
Services Office (MD-35), U.S. Environmental Protection Agency, Research Triangle Park NC 27711, or from
National Technical Information Services, 5285 Port Royal Road, Springfield VA 22161.
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ENVIRONMENTAL PROTECTION AGENCY
Background Information and Draft
Environmental Impact Statement
for New Residential
Wood Heaters
m" spared by:
:armer ' " (Date)
Director, Emission Standards Division
U. S. Environmental Protection Agency
Research Triangle Park, NC 27711
1. The standards of performance would limit emissions of particulate
matter from new residential wood heaters. Section 111 of the Clean Air
Act (42 U.S.C. 7411), as amended, directs the Administrator to
establish standards of performance for any category of new stationary
source of air pollution that ". . . causes or contributes significantly
to air pollution which may reasonably be anticipated to endanger public
health or welfare."
2. Copies of this document have been sent to the following Federal
Departments: Labor, Health and Human Services, Defense, Office of
Management and Budget, Transportation, Agriculture, Commerce, Interior,
and Energy; the National Science Foundation; and the Council on
Environmental Quality. Copies have also been sent to members of the
State and Territorial Air Pollution Program Administrators; the
Association of Local Air Pollution Control Officials; EPA Regional
Administrators; and other interested parties.
3. For additional information contact:
Mr. Rick Colyer
Standards Development Branch (MD-13)
U. S. Environmental Protection Agency
Research Triangle Park, NC 27711
Telephone: (919) 541-5262.
4. Copies of this document may be obtained from:
U. S. EPA Library (MD-35)
Research Triangle Park, NC 27711
National Technical Information Service
5285 Port Royal Road
Springfield, VA 22161
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Table of Contents
Category
Chapter 1.
Chapter 2.
Section
Section
Chapter 3.
Table 1.
Section
Section
Section
Section
Section
Section
Section
Section
Section
Section
Section
Section
Section
Section
Section
Section
Section
Section
Section
Section
Section
Section
Section
Introduction
Summary
1. Summary of Changes Since Proposal . . . .
2. Summary of Impacts of Promulgated Action
Summary of Comments and Responses
List of Commenters
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
Need for Regulation . . .
Opportunity for Public Comment .
Authority to Regulate
Composition of the Regulatory Negotiation Committee
Pollutants Regulated
Affected Facilities
Definitions
Best Demonstrated Technology
8.1 Catalytic
8.2 Noncatalytic
Format for the Standards
Certification Testing: General
Method 28
Method 5G
Method 5H
Relationship of Methods 5G and 5H
Altitude Effects
Laboratory Accreditation
Quality Assurance Procedures
Certification Procedures
Audit Procedures
Reporting and Recordkeeping
Labeling
Consumer Education
Cost and Economic Impacts
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1. INTRODUCTION
On February 18, 1987, the U.S. Environmental Protection Agency (EPA)
published in the Federal Register (52 FR 4994) "Standards of Performance for
New Stationary Sources; Residential Wood Heaters." These standards were
proposed under the authority of Sections 101, 111, 114, and 301 of the Clean
Air Act, as amended.
Because of the way these standards directly affect the public, EPA made
an extraordinary effort to inform and involve the public in the early stages
of the rulemaking. In addition to the August 2, 1985, Advance Notice of
Proposed Rulemaking, EPA convened a regulatory negotiating committee.
Representatives of all parties affected by the regulation were given the
opportunity to participate. This was the first NSPS to be developed by
regulatory negotiation. The general public was invited to attend and was
allowed opportunities to make presentations and to comment from the floor
during the committee's deliberations. Notice of these meetings was provided
in the Federal Register and in trade journals.
There was also public comment at each of two National Air Pollution
Control Techniques Advisory Committee meetings on the these standards. EPA
technical staff have been made available to respond by telephone and by mail
to interested members of the public and the news media.
Finally, public comments were solicited at the time of proposal. No
requests for a public hearing were received either by telephone or by
letter. However, public comment letters submitted during the comment period
have been individually reviewed by EPA. These comments, along with EPA's
responses, are summarized in this document. This document also contains
questions posed to the Agency on some aspects of the standard, especially
applicability, that have resulted in changes to the final rule.
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2. SUMMARY
Section 1. Summary of Changes Since Proposal.
There are many changes between the wording of the proposed regulation
(including test methods) and the promulgated regulation. Some of these, such
as the decision to exclude cookstoves from the regulation, are in response to
the written comments. Others are corrections of typographical errors or
incorrect cross-referencing. Most are clarifications to the applicability or
the certification provisions that were either ambiguous as proposed or were
found to be necessary in EPA's actual implementation experience, which has
been underway for several months. Each of these changes is within the general
agreements worked out by the regulatory negotiation committee. These changes
are summarized below in the order they appear in the regulation.
1. Section 60.530(c)(1). The words "and shall be certified by the
Administrator" were stricken because the phrase is redundant with the require-
ment that Oregon-certified woodstoves be exempted if certain conditions are
met.
2. Section 60.530(c)(l). New paragraphs (iv) and (v) were added
requiring applicants for Oregon "grandfather" exemptions to submit photographs
of the wood heaters, engineering drawings, a copy of the catalyst warranty (if
applicable), and statements affirming that the manufacturer will comply with
the continuing provisions of the regulation. The new Section 60.530(c)(l)(iv)
also clarifies that the catalyst warranty provisions apply to Oregon
grandfathered stoves. Finally, the new paragraph (v) requires that the
applicants for an Oregon grandfather exemption must submit a copy of the
Oregon certificate, engineering drawings and portions of the test report
related to the EPA burn rate criterion. In summary, these changes clarify
that Oregon-grandfathered wood heaters must comply with all requirements
except the certification testing and quality assurance emission testing
requirements.
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3. Section 60.530(c). A new paragraph (5) has been added allowing EPA
to revoke a certificate issued to an Qregon-grandfathered model if the manu-
facturer fails to comply with the labeling, reporting and recordkeeping, and
quality assurance provisions. Similar revocation authority for EPA-certified
wood heaters is already provided in Section 60.533(1).
4. Section 60.530(d). A new paragraph (5) has been added clarifying
that for purposes of the small manufacturer exemption, an importer is not a
manufacturer. Language was also added clarifying that foreign manufacturers
must export to the U.S. fewer than 2,000 stoves total to be eligible for the
small manufacturer exemption.
5, Section 60.530(e) through (g). The words "and the requirements of
60.533" were added to the export, research and development, and coal-only
heater exemptions to clarify that these appliances are exempt from the
certification requirements, as well as the emission limits.
6. Section 60.530(h). A new paragraph (h}{4) was added to include
cookstoves to the list of appliances that are exempted from the standards
altogether. This was done because comment letters and an examination of
cookstoves convinced EPA that these devices are substantially different from
the devices for which BDT has been identified and that a direct technology
transfer is not possible. Change number 8 below describes the characteristics
of cookstoves which differentiate them from wood heaters.
7. Section 60.531. Paragraph (a) under the definition of "coal-only
heater," which read "An opening for loading coal which is located near the top
or side of the appliance" was stricken because it was vague and ambiguous.
Also, the words "or a power-driven mechanical stoker" were added to the
renumbered paragraph(c) as another criterion for defining a coal-only stove.
As it is now written, a coal-only heater must have stokers or shaker grates,
but not necessarily both, to qualify for an exemption (as well as meeting the
other requirements).
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8, Section 60.531. A new definition, "cookstove," has been added:
"cookstove" means a wood-fired appliance that is designed primarily for
cooking food and that has the following characteristics: (a) an oven, with a
volume of 1.0 cubic feet or greater, and an oven rack; (b) device for measur-
ing oven temperatures; (c) flame path that is routed around the oven; (d)
shaker grate; (e) an ash pan; (f) an ash clean-out door below the oven; and
(g) the absence of a fan or heat channels to dissipate heat from the appli-
ance.
9. Section 60.531. The words "that is designed to be located outside
of ordinary living areas and that warms" were added to the definition of the
term "furnace" to help prevent circumvention of this exemption by
manufacturers who label their appliances as furnaces and who have their
appliances listed and tested as furnaces, but who are manufacturing appliances
which operate and function as woodstoves or fireplace inserts. Also, another
change to this definition allows manufacturers of bona fide furnaces to apply
for an exemption from the standards without having their appliances tested and
listed. The last sentence in the definition of furnace now reads: "The
appliance must be tested and listed as a furnace under accepted American or
Canadian safety testing codes unless exempted from this provision by the
Administrator. A manufacturer may request an exemption in writing from the
Administrator by stating why the testing and listing requirement is not
practicable and by demonstrating that his appliance is otherwise a furnace."
10. Section 60.531. The words "indoor cooking" have been removed from
the definition of wood heater to reflect the exclusion of cookstoves from the
regulation. Also, the 5 kg/hr minimum burn rate criterion for defining wood
heater has been clarified to indicate that the burn rate must be determined by
EPA Method 28A at an accredited laboratory. This clarification does not
necessarily require that a test be performed or prevent a manufacturer from
testing elsewhere, but is necessary to provide a clear method when needed for
enforcement/dispute resolution. Also see change number 25 below. Finally,
the 800 kg maximum weight criterion has been clarified to avoid circumvention
by adding the words: "In determining the weight of an appliance for these
purposes, fixtures and devices that are normally sold separately, such as flue
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pipe, chimney, or masonry components that are not an integral part of the
appliance or heat distribution ducting, shall not be included."
11. Section 60,533(b). Several requirements and clarifications to the
proposed requirements for certification applications were added. These
include a requirement that two copies of the application be submitted; that
two color photographs of the tested unit be submitted, one showing a front
view and the other a side view [this does not imply that the color of the
stove has any bearing on emissions (i.e., production line stoves need not be
the same color as the tested unit)]; that manufacturers do not necessarily
need to develop new engineering drawings, but that the existing assembly or
design drawings should be labeled to indicate dimensions and tolerances of all
parameters affecting emissions (i.e., Section 60.533(k)); that a program to
ensure consistency in any gap in the catalyst bypass mechanism be included;
that test report data be submitted in a form recommended by EPA in order to
expedite the review of certification tests; that photographs of the test fuel
load for each run be included in the test report; that the manufacturer
describe how the catalyst is replaced, and that the application include
several affirmations that the manufacturer will comply with the on-going
requirements (e.g., recordkeeping and reporting) of the regulation. The
purpose of the affirmations is to remind the manufacturer of his continuing
obligations under the standards. None of these changes is expected to add
measurably to the applicant's burden and, with the exception of the fuel load
photograph requirement, all are part of EPA's recommended application forms
currently being used by manufacturers applying for certification. The
requirements should result in more uniform test reporting which should
expedite the application review process.
12. Section 60.533(b). A new paragraph (b)(12) has been added to the
requirements for manufacturers seeking EPA certification as follows: "a
written estimate of the number of wood heaters that the manufacturer antici-
pates will be manufactured annually for the first two production years.
Compliance with this provision may be obtained by designating one of the
following ranges: (i) fewer than 2,500, (ii) 2,500 to 4,999, (111) 5,000 to
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9,999, (iv) 10,000 to 49,999, and (v) 50,000 or greater." EPA recognizes that
these data are sensitive and proprietary and will treat them as confidential.
These data are necessary in order for EPA to enforce the manufacturers'
QA provisions in Section 60.533(o), which are based in part on production
volumes. It should be noted that the standards do not require reporting of
manufacturers' QA test results, and EPA does not intend to request routinely
the results of such testing.
13. Section 60.533(b)(14). A new paragraph (b)(14) has been added which
specifies that a manufacturer seeking certification of model lines under
Section 60.533(e) to meet the emission limits under Section 60.533(b) must
provide a statement that the manufacturer has entered into a contract with an
accredited laboratory which satisfies the requirements of paragraph (g) of
Section 60.533.
14. Section 60.533(e)(iii). A sentence was added stating that the
program to ensure consistency in catalyst bypass gaps required under paragraph
(b)(3)(iii) of Section 60.533 shall be deemed a tolerance specified in the
certified design.
15. Section 60.533(f)(l). The contents of the certification test
notification by the manufacturer to EPA are detailed in this additional
language. It now reads as follows: The certification test must be "announced
to the Administrator in accordance with Section 60.534(e)."
16. Section 60.533(g). A requirement was added that specifies that
manufacturers must enter into a contract with an accredited laboratory which
covers the cost of Random Compliance Audit (RCA) testing. Under the contract,
the laboratory must agree that, if and when EPA requires an RCA test to be
conducted, the laboratory will either: (1) conduct the test at no further
expense to the manufacturer, or (2) pay the manufacturer the reasonable cost
of the test if EPA selects another laboratory to test the model covered by the
contract. This arrangement was designed to overcome Office of Management and
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Budget (OMB) concerns about the escrow account arrangement included in the
proposal by shifting the primary obligation from the testing laboratory to the
manufacturer. The original language obligated the laboratory to conduct an
RCA test for EPA and to place funds in an escrow account under the
administration of EPA for such purposes. This arrangement was considered by
OMB to be possibly an illegal supplemental appropriation of the Federal
budget. The revised provision makes clear that the arrangement for financing
RCA tests must be between the manufacturer and the laboratory rather than
between the laboratory and EPA.
17. Section 60.533(h)(3)(ii)(A). This change simply brings those wood
heaters certified under the alternative certification procedures for undue
certification delays (i.e., so called "logjam stoves"), under the same data
requirements for applications as are the regularly certified wood heaters.
18. Section 60.533(h)(4)(iv). This provision specifies the condition
that shall cause a certificate issued under the alternative certification to
expire. To ensure that a manufacturer does not deliberately extend the
testing period or withdraw his wood heater from testing in order to avoid
revocation based on high emissions, provisions were added that alternative
certification would expire if the manufacturer delays testing by a period of
14 days or if he withdraws his wood heater from testing.
19. Section 60.533(k)(2). Several changes were made to this section
that involve the identification of components that are presumed to affect
emissions. The first change is to delete language that required manufacturers
to meet the tolerances that they state in their engineering drawings rather
than the maximum allowable tolerances of + 1/4 inch and + 5 percent of the
cross-sectional area. As proposed, the provision would have rewarded
manufacturers with less stringent quality assurance and could result in uneven
enforcement. The second change adds "catalyst bypass gaps" to the list of
components. The EPA has data showing that variations in catalyst bypass gaps
can significantly affect emissions from otherwise similar wood heaters.
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Finally, three other components were added, as follows: "(ix) outer shielding
and coverings: dimensions and location, (x) fuel feed system: for wood
heaters that are designed primarily to burn wood pellets and other wood
heaters equipped with a fuel feed system, the fuel feed rate, auger motor
design and power rating, and the angle of the auger to the firebox, and (xi)
forced air combustion system: for wood heaters so equipped, the location and
horsepower of blower motors and the fan blade size." Item (ix) is designed to
account for model lines that may have an optional shell or shielding additions
that could affect the heat transfer characteristics of the wood heater (as
opposed to minor placement differences on soapstone wood heaters, for
example). Any deviations that exceed the allowable tolerances of the physical
parameters listed in paragraph (k) on wood heater models will result in
requiring that the model be certified as a separate model line, unless it is
demonstrated (primarily with test data) to the Administrator's satisfaction
that such changes would not be expected to affect emissions.
20. Section 533(o)(3)(ii). A change was made allowing manufacturers to
use either approved particulate sampling method (i.e., Methods 5G or 5H) in
their quality assurance programs.
21. Section 60.533(p)(l)(i). Language was added to Section
60.533(p)(l)(i) which states that the Administrator shall not select more than
one model line under the RCA program for every five certified model lines
tested by each laboratory. This provision was added to limit the liability of
manufacturers and laboratories for the cost of RCA testing.
22. Section 60.533(p)(3)(ii). Language was added to clarify that the
expense of RCA testing is ultimately the responsibility of the manufacturer.
The new language states that the manufacturer may require the laboratory that
conducted certification testing on their model lines to absorb the reasonable
test cost as part of the laboratory's testing fee by means of the contract
required of manufacturers under Section 60.533(g). If the laboratory with
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which the manufacturer had a contract is bankrupt or is otherwise legally
unable to meet its contractual obligation, no RCA tests will be conducted on
wood heaters tested by that laboratory,
23. Section 60.533(p)(3)(iii). A change was made to clarify that if
the certification test was conducted with more than one method, the audit
tests may be conducted with either test method, at EPA's discretion.
24. Section 60.533(p)(4)(iv). Removed.
25. Section 60.534(c). It is not necessary for manufacturers of
wood-fired appliances that are not subject to this regulation to demonstrate
that their appliance is not covered unless specifically required to do so by
EPA enforcement authorities. However, some manufacturers of appliances that
appear to be similar to facilities affected by the regulation want EPA to
document, by way of a letter, that their appliances are not covered. In those
cases where testing is required to determine applicability, EPA is requiring
that the testing be done in an accredited laboratory. For that reason the
following sentence was added to Section 60.534(c). "If such a determination
is necessary, this test shall be conducted by an accredited laboratory."
26. Section 60.534(e). This paragraph was revised to address two
problems that EPA has been experiencing in the certification testing program.
The first is the frequent rescheduling of certification tests without
sufficient notice, causing EPA test observers to appear for a test which had
been rescheduled without the Agency's knowledge. To address this problem, a
provision was added stating that failure to notify EPA of a schedule change at
least 14 days before the revised date will result in voiding the original
notification and will necessitate a second notification. The second problem
is the inadequate distinction between a laboratory's research and development
precertification testing, on the one hand, and certification testing, on the
other. In the first case, the lab serves as an advisor to the manufacturer;
in the second case, the lab should be an unbiased tester. To avoid the
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practice of deciding after the fact whether a particular test run was a
certification or a R&O test run, a provision was added clarifying that
certification testing is presumed to begin on the date specified in the test
notification.
27. Section 60.534(f). This new paragraph was added to address what EPA
believes to be a potentially serious problem with the integrity of the certi-
fication testing process. The problem arises from the influence that
manufacturers can exert on the conduct and outcome of the test. The
regulatory negotiation committee considered barring manufacturers from the
test site, but did not do so in light of arguments by manufacturers that:
(1) they had a right to observe the tests they are paying for and that affect
their livelihoods; and (2) that the manufacturers are uniquely qualified to
help the laboratory personnel make the initial air settings during the
pre-burn phase that will allow the wood heater to achieve the correct burn
rate category. The new paragraph (f) retains these two functions while
avoiding undue interference in the particulate sampling phase of the testing.
Finally, the new paragraph (f) reinforces the committee's decision that the
operating instructions for lab personnel should be consistent with the
operating instructions provided by the manufacturer in the owner's manual,
except to the extent they address details of the tests that would not be
relevant to consumers.
28. Section 60.535(b)(l). This paragraph has been revised to eliminate
the need for prior accreditation by the National Voluntary Laboratory
Accreditation Program (NVLAP) as a condition for EPA laboratory accreditation,
but to retain the substantive criteria for accreditation that NVLAP would have
required. The EPA and both industry and laboratory owners, as evidenced in
written comments, have determined this is unneeded and would be a costly
duplication.
29. Section 60.535{b)(3). A paragraph was added to require laboratories
to agree to enter into the same contract with manufacturers as required under
Section 60.533(g).
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30. Section 60.535{b)(4). Removed.
31. Section 60.535(b). Paragraphs (b)(8), (b)(9), and (b)(10) were
added to the conditions for accreditation. Paragraph (b)(8) requires the lab
to agree to allow EPA to observe certification testing and paragraph (b)(9)
reinforces the need for labs to comply with reporting and recordkeeping
requirements. Paragraph (b)(10) requires the lab to agree to accept the
reasonable cost of one RCA test if it is selected to conduct the RCA test of a
model line originally tested for certification at another laboratory.
32. Section 60,535(d). This paragraph has been removed to account for
the elimination of NVLAP accreditation.
33. Section 60.535(e)(l)(1v). Removed.
34. Section 60.535(e)(2). To avoid giving a laboratory an incentive to
unduly delay the revocation process, the following sentence was added:
"However, if revocation is ultimately upheld, all tests conducted by the
laboratory after written notice was given may, at the discretion of the
Administrator, be declared invalid."
35. Section 60.535(f)(3). This paragraph has been removed to account
for the elimination of NVLAP accreditation.
36. Section 60.535(g). This paragraph was revised to clarify that the
sealing of the tested wood heater should occur immediately upon completion or
suspension of the certification test and that the laboratory should use its
own lab-specific seal.
37. Section 60.536(h)(2). A sentence was added to provide a means under
which Oregon-weighted results can be presented in terms of the EPA weighting
and standards.
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38. Section 60.536{h)(3). Two sentences were added requiring Qregon-
grandfathered wood heaters to use the default efficiency values (as must
regularly certified models in the absence of an approved efficiency test) and
setting pellet stove default efficiencies at 78 percent. This value was
obtained using the same approach used to set catalytic and noncatalytic
default efficiency values,
39. Section 60.536(j)(7). To address a problem which has occurred in
Oregon woodstove certification program regarding the temporary labels or hang
tags, the following language was added: "To prevent the removal or destruc-
tion of temporary labels on wood heaters displayed by retailers, adhesive
backings and other means to preserve the label may be used."
40. Section 60.536(k)(l). A sentence was added clarifying that the
written instructions the manufacturer provides in the owner's manual should be
consistent with operational instructions provided to the testing laboratory,
except for details of certification testing not relevant to the ultimate
purchaser.
41. Section 60.536(1). This new paragraph was added to clarify that
second-hand wood heaters do not need temporary labels if they are resold.
42. Section 60.537(a)(l). A sentence was added to this paragraph
clarifying that Oregon-grandfathered wood heaters are subject to the nontest-
related reporting and recordkeeping requirements.
43. Section 60.537(b)(2)(i). This paragraph was expanded to clarify
that the laboratory should report its testing schedule to EPA on the basis of
whether the scheduled tests are EPA certification tests, Oregon certification
tests, or research and development tests. This revision is necessary to allow
EPA to determine which tests it chooses to observe and to better understand
and confirm reported estimated lead times for certification testing.
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44. Section 60.537{c), This paragraph was revised to require that the
manufacturer retain the sealed stove rather than making the location of
retention optional (i.e., at the lab or at the manufacturer's facility). For
imported stoves, the location of the sealed stove will be the point of import
(e.g., warehouse where imported stoves are first stored prior to
distribution). This will enable EPA to better enforce the quality assurance
provisions by being able to conduct parameter inspections using the tested
wood heater to compare against production line wood heaters.
45. Section 60.537(d). This paragraph was eliminated in response to a
comment by OMB that the burden on retailers caused by the requirement to
maintain records on who purchased their wood heater was excessive. The EPA
believes this requirement is not necessary because it expects these records to
be needed very rarely. Most commercial owners keep such records and EPA has
the authority under Section 114 to obtain such records.
46. Section 60.537(e)(l). The deadline on the production volume report-
ing requirement for manufacturers seeking the small manufacturer exemption has
been changed from September 1, 1988, to August 1, 1988.
47. Section 60.537(e)(4). A new paragraph (e)(4) has been added
requiring those manufacturers who intend to apply for the small manufacturer
exemption to notify EPA of their intent by July 1, 1988.
48. Section 60.538(d)(iii)(2). A sentence was added clarifying that
used wood heaters (i.e., used by noncommercial owners) are not required to be
accompanied by a temporary label.
49. Section 60.539(b). A phrase has been added requiring one who
petitions for a hearing to provide the basis for his objection.
50. Section 60.539a. This new section was added pursuant to EPA's new
policy to state in NSPS the extent to which the implementation and enforcement
of the regulation will be delegated to the States. For this regulation,
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applicability determinations, the certification testing and review program,
laboratory accreditation program, collection of reports, the hearings and
appeal process, and all other actions by or to the Adminstrator will all be
conducted by EPA exclusively.
51. Section 60,539b. This new section identifies which of the General
Provisions (Subpart A of Part 60) do not apply for purposes of these
standards.
52. Appendix I - Section 2.1. In response to a comment recommending
improved label appearance, a requirement that helvetica type font be used was
added. Also, seven figures illustrating various label types (e.g., catalytic
or noncatalytic) were slightly revised in appearance, but not in substance.
53. Method 5G Section 2.1.1. The words "no longer than" were inserted
to allow for probes shorter than 24" to be used.
54. Method 5G Section 2.1.1. A sentence was added to make the probe
more corrosion resistant.
55. Method 5G Section 2.1,4. Teflon was added to the allowable gasket
material. This was an oversight in the original version.
56. Method 5G Section 2.1.5. The tolerances on thermocouples and
thermometers were changed from 1,0% of absolute temperature to 1.5% of
absolute temperature. This is in keeping with other EPA methods and actual
practice in the field.
57. Method 5G Section 2.1.5. A sentence was added allowing the filter
temperature to be taken prior to the first filter if desired. The temperature
specifications have not changed and this location would record a temperature
at least as high as the original placement.
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58. Method 5G Section 2.1.6. A sentence was added to require a
monitoring system that would demonstrate that the moisture had been removed
prior to measurement with the dry gas meter.
59. Method 5G Section 2.1.9. Same reason as comment 56.
60. Method 56 Section 4.1.1. A sentence was added at the end of the
section to clarify the operation of the wood heater during the draft
determination procedure.
61. Method 5G Section 4.1.2. Wording was added to clarify the operation
of the wood heater during the smoke capture procedure.
62. Method 5G Section 4.3.3.1. A sentence was added allowing
leak-checks to be performed at a lower vacuum prior to the testing. This is
in keeping with the low vacuums expected during the dilution tunnel testing.
63. Method 5G Section 4.3.3.2. A sentence was added allowing leak
checks performed after the test to be performed at lower vacuums for the same
reasons as comment 62.
64. Method 56 Section 4.3.5. A paragraph was added to allow for
proportional sampling rate calculations to be performed with the data obtained
from rotameters. This does not eliminate the need for a dry gas meter which
is to be used for volume determinations. The accuracy of the proportional
rate determination is in keeping with the rotameter accuracy.
65. Method 56 Section 4.3.5. "Or upstream of" was added to be
consistent with Section 2.1.5. See comment 57.
66. Method 56 Section 4.4. Larger volumes of Acetone blank were
allowed, since this would increase the accuracy of the blank.
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67. Method 5G Section 4.4. The phrase "about 50 m}" was changed to
"about 50 ml."
68. Method 5G Section 4.5. Several changes were made affecting the
desiccation and weighing of the sample fractions in response to comments. The
change will allow more flexibility in the timing of the weighings.
69. Method 5G Section 5.1. There was a sentence added to include the
inspection as a quality control measure of standard pitot tubes allowed in the
equipment sections.
70. Method 56 Section 5.2.1. A clarification was added to highlight the
most recent changes in calibration standards.
71. Method 5G Section 5.5. A clarification was added for the use of
mercury barometers
72. Method 5G Section 5.6. A quality control measure was added to
ensure accurate sample catch weight determinations.
73. Method 56 Section 6.1. A clarification was highlighted as
29 g/g mole, the assumed dry gas molecular weight.
74. Method 56 Section 6.7. A clarification was added to the section to
accommodate commenters who collect data more frequently than required by the
method.
75. Method 5G Section 7.1. Several changes were made to clarify and
specify the references of this section.
76, Method 56 Section 7.2.4. A quality control measure was added to
provide for improved cleanliness and desiccation of the probes.
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77. Method 5H Section 1.2. Maximum temperatures were placed in the
method rather than tolerances on the temperatures to conform to the intent of
the method.
78. Method 5H Section 2.1.1. The probe nozzle is now optional due to
the nature of woodsmoke. The mean particle diameter is 0.17 microns which
causes woodsmoke to act as a gas.
79. Method 5H Section 2.2.3. A quality control measure was added to
provide for accurate readings from continuous emission monitor (CEM)
analyzers.
80. Method 5H Section 2.3.1. Stainless steel and glass are manditory
for the construction of the rotameter. This was done so the calibration could
be changed to semiannual from once a test series,
81. Method 5H Section 2.3.3. Use of a desiccant other than silica gel
is required to avoid sample contamination by silica gel.
82. Method 5H Section 2.3.6. Use of a mass balance approach is deleted
because it has not been demonstrated to be accurate for determining
proportionality in woodstove testing.
83. Method 5H Section 3.3.1. Specifications were added to the
calibration gases which are compatible with other EPA reference methods and
protocols. The calibration frequency was relaxed as the cylinders are not
subject to change.
84. Method 5H Section 4.2. The drift tolerances were changed to make
them more consistent with the on-going procedure.
85. Method 5H Section 5.1.2. A sentence was added to clarify the
distance measured from the wood heater scale.
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86. Method 5H Section 5.1.4.1. Same as comment 62.
87. Method 5H Section 5.1.4.3. Same as comment 63.
88. Method 5H Section 5.1.6. The new tolerances add more flexibility in
the probe locations.
89. Method 5H Section 5.2.1. In response to comments, the initial
sampling rate was changed to be more in keeping with actual practice.
90. Method 5H Section 5.2.2.1. Defines the test fuel charge weight be
recorded as wet and eliminates the alternative of measuring the wood
composition. This revision is consistent with the data base on which the
standards were based.
91. Method 5H Section 5.2.3. Several changes were made to this section
to clarify or highlight previous changes.
92. Method 5H Section 5.3. Several changes were made in the desiccation
and weighing of the samples to make them consistent with Method 5G.
93. Method 5H Section 5.3. A sentence was added to caution test labs to
clean off stopcock grease so it does not add to the sample weight.
94. Method 5H Section 6.2. The probe heater calibration is' optional,
because the probe heater is no longer mandatory.
95. Method 5H Section 6.6. The tracer gas injection rotameter
calibration was relaxed to semiannual to be in keeping with data showing no
change.
96. Method 5H Section 6.9. Several changes were made to clarify this
section.
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97. Method 5H Section 6,10. Calibration specifications were added for
the analytical balance as a quality control measure.
98. Method 5H Section 7.1. Changes were made in the gram atoms of
carbon to be used in the flow calculation. It is now a constant as the
measuring of the wood composition has been removed. The assumed mole fraction
of HC for pellet-fired wood heaters was added.
99. Method 5H Section 7.9. The temperature portion of the sample flow
calculation (equation 5H-6) was removed in response to commenters.
100. Method 5H Section 7.13. The proportional rate calculation was
changed to remove the temperature measurement and to format the equation in
the most accurate form.
101. Method 5H Section 7.14. The acceptability values were changed to
reflect actual procedures and practices.
102. Method 28 Section 2.11.1 was revised by adding an explanation of
the top of the wood heater door.
103. Method 2.11.1. The word "permanent" was added to be consistent
with Section 6.2.4 of Method 28.
104. Method 28 Section 2.12, was revised by deleting reference to indoor
cooking, wood burning units.
105. Method 28, Section 2.13. A definition of pellet burning wood
heaters was added as follows: "Pellet burning wood heater. A wood heater
which meets the following criteria: 1) the manufacturer makes no reference to
burning cordwood in advertising or other literature, 2) the unit is safety
listed for pellet fuel only, 3) the unit operating and instruction manual must
2-18
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state that the use of cordwood is prohibited by law, and 4) the unit must be
manufactured and sold including the hopper and auger combination as integral
parts."
106. Method 28 Section 3.1, was revised to allow labels from
laboratories other than Underwriters Laboratories to be used to indicate
conformance with the U.I. standard.
107. Method 28 Sections 3.3 and 3.4, were revised by changing the
specification for temperature gauges to be consistent with other EPA methods.
108. Method 28 Section 3.7, was revised to allow use of less sensitive
air velocity measurement devices.
109. Method 28 Section 3.9, was revised by adding stricter
specifications for the draft gauge.
110. Method 28 Section 4.1.1, was revised by adding a paragraph allowing
the use of other than single wall steel flue pipe if specified by the
manufacturer.
111. Method 28 Section 4.1.2, was revised to specify that only
facilities with artificially induced barometric pressure shall comply with the
barometric pressure limit.
112. Method 28 Section 4.2.3. The English units were added in the
parenthesis.
113. Method 28 Section 4.3.1. The definition is now only the length
since that is always the longer dimension.
114. Method 28 Sections 4.3.1 and 6.2.55 were revised to clarify the
intent of the test fuel crib specifications.
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115. Method 28 Section 5.2, was revised by adding a definition of the
evidence needed to demonstrate that the minimum burn rate cannot be achieved.
116. Method 28 Section 5.2. A sentence was added to define minimum burn
rates greater than 0.8 kg/hr, and the reporting requirements were defined more
clearly.
117. Method 28 Section 6.1. The aging procedure is now only to be
conducted by an accredited laboratory and not a manufacturer. This was done
due to the increased reporting requirements and complexity of the procedure.
118. Method 28 Section 6.1.1, was revised to require specific data
collection and measurement intervals during the catalyst and wood heater
aging. Reporting requirements were also clarified.
119. Method 28 Section 6,2.1, was revised to require that the flue be
cleaned prior to each certification test. This requirement was inadvertently
omitted from the proposal.
120. Method 28 Section 6.2.2, was revised with additional explanation
about the location of the surface temperature monitors.
121. Method 28 Section 6.2.2. The word "generally" was replaced by
"centrally" to better explain the location of the catalyst exhaust temperature
monitor.
122. Method 28 Section 6.2.3, was revised by clarifying the location
specifications for the facility temperature monitor, and by specifying that
flue draft be measured and recorded during the test run.
123. Method 28 Section 6.2.4, was revised by clarifying the measurement
of firebox volume around obstructions in the firebox.
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124, Method 28 Section 6.2,5, was revised by clarifying the procedures
for measuring wood moisture and by allowing removal of spacers from the top of
the test fuel crib.
125, Method 28 Section 6.2.7, was revised by adding detail to the
procedure for determining the effect of secondary air adjustments on wood
heater burn rate.
126. Method 28 Section 6.3.1. The pretest fuel requirements were
changed to allow the use of 4x4's. This fuel has different burning
characteristics than the use of 2x4's; thus, the pretest could be more like
the test if desired.
127. Method 28 Section 6.3.2, was revised by adding a definition of coal
bed raking, by expanding the data recording requirements during the pretest
period, by adding clarifying language concerning the definition of uniform
charcoalization, and by adding a definition of the initial wood heater weight
that allows for ash to be included in the tare weight of the stove if it is in
the manufacturer's instructions.
128. Method 28 Section 6.4.1, was revised by editing the language
defining the test run start procedure, and by adding clarification on the
placement of the test fuel crib in the wood heater at the start of the test
run.
129. Method 28 Section 6.4.1. A sentence was added to clarify the wood
load procedures for unusual firebox design.
130. Method 28 Section 6.4.2. Two changes were made in the pretest fuel
to allow the laboratories to use fuel similar to that being used for the test
fuel change.
131. Method 28 Section 6.4.2. Two sentences were added to clarify the
reporting requirements.
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132. Method 28 Section 6.4.3, was revised with the addition of a percent
of fuel weight limit to the definition of no weight change. This was done in
order to add flexibility to the procedures for very large test fuel charges.
133. Method 28 Section 6.4.S. The words "with the blower" are changed
to "without the blower" to be consistent.
134. Method 28 Section 6.4.6, was revised by expanding the definition of
the end of the test run.
135. Method 28 was revised by adding a new Section 6.7 describing
procedures applicable for testing of pellet-burning wood heaters.
136. Method 28 Section 7.1, was revised by clarifying the acceptability
limits for calibration of the platform seal.
137. Method 28 Section 7.5, was revised by allowing the use of
manufacturer's recommended procedures in calibrating the facility air velocity
measurement device.
138. Method 28 Section 8.1, was revised by requiring linear
interpolation in determining the applicable probability values for burn rate
between those listed on the table in the method.
139. Method 28 Sections 8.4.4 and 8.4.5, were revised by addition of
specific items and general categories to be included in the certification test
report.
140. Method 28 Figure 28-4, was revised by adding a column for reporting
the draft data.
141. Method 28A Section 1.1 and title. Minimum achievable burn rate was
added to the purpose and title of Method 28.
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142. Method 28A Section 3.2, 3.3, 5.3, 5.4.2, 7. Method 5H Sections
2.2.1 - 2.2.3 are referenced rather than methods 3A and Method 10. This was
done to allow for the woodstove laboratory equipment to be used. Sentences
were added to clarify the instruments and methods used for this procedure and
to make this method more consistent with the other wood heater methods,
143. Method 28A Section 5.3. The sampling procedures were changed to
reflect a time weighted average which is consistent with the calculation.
144. Method 28A Section 5.3. Quality assurance specifications were added
for gas concentration measurement procedures.
145. Method 28A Section 5.5.1.2. The words "the fuel factor should be
reviewed and verified" are deleted because this quality assurance check is not
necessary. The acceptability criteria and alternatives are added to clarify
the EPA position.
146. Method 28A Section 6.1. The assumed mole fractions of hydrocarbons
were updated to include pellet-fired wood heaters and to make the other
factors consistent with Method 5H.
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Section 2. Summary of Impacts of Promulgated Action.
Alternatives to the Promulgated Action
Because this rule was prepared on an expedited schedule through
regulatory negotiation, the regulatory alternatives to the standards were
discussed and the regulatory approach agreed upon by the regulatory
negotiation committee (defined under "Public Participation" in the
promulgation preamble). Section L, "Selection of BDT," of the proposal
preamble summarizes the various levels of control and control options
considered. Section 1 of Chapter 2 of this background information document
summarizes the changes in the standards since proposal.
Environmental Impacts of the Promulgated Action
The final standards are estimated to reduce atmospheric emissions of PM
from catalytic and noncatalytic wood heaters by 82 and 72 percent,
respectively, for the 1988 standards. Catalytic and noncatalytic wood heaters
complying with the 1990 standards will emit at least 86 and 75 percent less
PM, respectively, than conventional wood heaters. The EPA estimates that
nationwide PM emission reductions in the fifth year of 395 Gigagrams per year
(436,000 tons per year) will result from promulgation of these standards.
Energy and Economic Impacts of the Promulgated Action
Energy and economic impacts resulting from (the standards are discussed in
the promulgation preamble and have not changed substantially since proposal.
Irreversible and Irretrievable Commitment of Resources.
These standards would not preclude the development of future control
options nor would they curtail any beneficial use of resources. Rather,
implementation of the standards would cause less wood to be consumed for
heating purposes due to the improved efficiency of regulated woodstoves. The
standards do not involve short-term environmental gains at the expense of
long-term environmental losses. The standards yield successively greater
2-24
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short- and long-term environmental benefits, with the alternative upon which
the final standards are based providing the greatest benefits. No changes in
these considerations have resulted since proposal of the standards.
Environmental and Energy Impactsof DelayedStandards.
Delay in promulgation of the standards would cause a delay in realizing
the beneficial impacts associated with the standards, including decreased
levels of PM emissions. No changes in the potential effects of delaying the
standards have occurred since proposal.
Urban and Community Impacts.
There are no urban and community impacts attributable to the promulgated
standards other than the improvement in ambient air quality and decreased
property damage (i.e., less sooting) in neighborhoods where woodstoves are
widely used.
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3. SUMMARY OF COMMENTS AND RESPONSES
Comment letters on the proposed standards were received from industry,
trade associations, State and local regulatory agencies, citizens groups,
and individuals. Table 1 lists the commenters and gives their addresses.
Section 1. Need for Regulation.
1.1 Commenter IV-D-37.
Comment: One commenter stated that no accurate or reliable data base
exists to show that emissions from woodstoves are harmful. This commenter
contended that recent information from Missoula, Montana, and other locales
indicates that woodsmoke may not be as big a problem as originally thought.
(IV-D-37)
Response: Emissions from wood heaters are significant. The national
annual partial!ate matter (PM) emission total from all wood heaters is
estimated to be about 2.5 Mg (2.8 million tons). Almost all PM emissions
from wood heaters are smaller than 10 microns. PM of this size is a special
concern because it can penetrate to the trachea-bronchial and alveoler
regions of the lungs where it may take years for the body to repair the
damage. Exposure to PM of this size can increase coughing and chest
discomfort, aggravate cardiovascular diseases, and may increase the adverse
health effects-of gaseous air pollutants. For further discussion of PM,Q
emissions, see 52 FR 24634, July 1, 1987.
In addition to PM, wood heaters emit large quantities of carbon
monoxide (CO) and polycyclic organic materials (POM). POM is a class of
compounds containing carcinogens. Wood heaters account for most of the
estimated POM emitted by stationary sources.
1.2 Commenter IV-D-37.
Comment: The commenter also claimed that there was no reasonable
assurance that the regulation would improve air quality because it deals
with only one of a four-part system, composed of the user, fuel, chimney,
3-1
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TABLE 1. LIST OF COMMENTERS
Docket Number A-84-49
Docket Item Number Commenter/Affi1i ation
IV-D-1 George Akers
Meridian Consolidated Industries,
Inc.
1605 South 93rd Street
Building 6, Unit U
Seattle, Washington 98108
IV-D-2 Masonry Stove Builders
Post Office Box 4295, Station E
Ottawa, Ontario
Canada K1S 5B3
IV-0-7 Ed Wadington, President
Energy and Environmental Measurement
Corporation
3925 Placita de la Escarpa
Tucson, Arizona 85715
IV-D-8 George Akers, President
Meridian Consolidated Industries,
Inc.
1605 South 93rd Street,
Building G, Unit U
Seattle, Washington 98108
IV-D-9 Gary M. Hazard, Vice President
Hearthstone Company
Hearthstone Way
Morrisville, Vermont 05661
IV-D-10 Harry E. Featherstone, President
The Will-Burt Company
169 South Main Street
Orrville, Ohio 44667
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TABLE 1. LIST OF COMMENTERS (CONTINUED)
Docket Number A-84-49
Doc_ke t It em Number Commenter/Af f 111 at i on
IV-D-11 William F, Cox
Knight Energy Systems, Inc.
Post Office Box 797
Grifton, North Carolina 28530
IV-D-12 W. H. Pickering
Association of Pellet Fuel Industries
905 Greg Street
Sparks, Nevada 89431
IV-D-13 John Todd, Acting Director
Centre for Environmental Studies
University of Tasmania
Box 252C, GPO
Hobart, Tasmania
Australia 7001
IV-D-14 John Hucsko
Elmira Stove Works
22 Church Street West
Elmira, Ontario
Canada N3B 1M3
IV-D-15 Richard A. Russo, President
Russo Corporation
87 Warren Street
Randolph, Massachusetts 02368
IV-D-16 James C. Hardin, President
National Steelcrafters of Oregon
Post Office Box 2501
Eugene, Oregon 97402
IV-D-17 D. F. Kininmonth, Minister
New Zealand Embassy
37 Observatory Circle, N.W.
Washington, D.C. 20008
IV-D-18 Carol W. LaGrasse
Stony Creek Town Board
Stony Creek, New York 12878
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TABLE 1. LIST OF COMMENTERS (CONTINUED)
Docket Number A-84-49
Docket Item Number Commenter/Affi11 ation
IV-D-19 Kenneth M. Suesse
Technical Products Division
Corning Glass Works
Corning, New York 14831
IV-D-20 Richard A. lusso, President
The Russo Corporation
87 Warren Street
Randolph, Massachusetts 02368
IV-D-21 Brad Michael
Elmira Stove Woods
22 Church Street West
Elmira, Ontario
Canada N3B 1M3
IV-D-22 Gary M. Hazard, VP
Hearthstone Company
Hearthstone Way
Morrisville, Vermont 05661
IV-D-23 Bradley J. Beckham, Director
Air Pollution Control Division
Colorado Department of Health
4210 East llth Avenue
Denver, Colorado 80220
IV-D-24 Eric R. Flowers
Tennessee Dept. of Health and
Environment
Customs House
701 Broadway
Nashville, Tennessee 37219
IV-D-25 OMNI Environmental Services
10950 S. W. 5th Street
Suite 245
Beaverton, Oregon 97005
IV-D-26 John K. Kowalczyk
Oregon Department of
Environmental Quality
811 S.W. Sixth Avenue
Portland, Oregon 97204
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TABLE 1. LIST OF COMMENTERS (CONTINUED)
Docket Number A-84-49
Docket Item Number Commenter/Affi1i ation
IV-D-27 W.S. Metes
Underwriters Laboratories, Inc.
333 Pfingsten Road
Northbrook, Illinois 60062
IV-D-28 David E. Menotti,
Counsel for Wood Heating Alliance
Verner, Liipfert, Bernhard, McPherson
and Hand, Chartered
Suite 1000
1600 L. Street, N.W.
Washington, D.C. 20036
IV-D-29 NESCAUM
85 Merrimac Street
Boston, Massachusetts 02114
IV-D-30 Marian S. English
17908 S.E. First Street
Camas, Washington 98607
IV-D-31 Richard S. Valentine
Salt Lake City-County Health Dept.
610 South 2nd East
Salt lake City, Utah 84111
IV-D-32 Norm Covell, Air Pollution
Control Officer
County of Sacramento
9323 Tech Center Drive, Suite 800
Sacramento, California 95826
IV-D-33 Rod Webner, Product Sales Manager
The Will-Burt Company
169 South Main Street
Orrville, Ohio 44667
IV-D-34 Alan Atemboski, Technical Director
Lopi Energy Systems West, Ltd.
10850 117th Place N.E.
Kirk!and, Washington 98033
3-5
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TABLE 1. LIST OF COMMENTERS (CONTINUED)
Docket Number A-84-49
Docket Item Number Commenter/Aff. 111 at.1 on
IV-D-35 Stockton G. Barnett, President
Barnett Environmental and Energy
Consultants, Inc.
8411 Rockspring Drive
Chagrin Falls, Ohio 44022
IV-D-36 Claren Lehman
Hitzer, Inc.
269 East Main Street
Berne, Indiana 46711
IV-D-37 Carl D. English, President
Homestead Research, Inc.
17908 S.E. First Street
Camas, Washington 98607
IV-D-38 Charles E. MacArthur, President
The Dover Stove Company
Main Street, Box 217
Sangerville, Maine 04479
IV-D-39 Robert W. Chapman, Senior Engineer
Sweet Home Stove Works, Inc.
1307 Clark Mill Road
Sweet Home, Oregon 97386
IV-D-40 Peter von Conta, General Manager
Vermont Technology Group, Inc.
RFD il, Post Office Box 80H
Morrisville, Vermont 01661
IV-D-41 Energy and Environmental
Measurement Corporation
1744 Mullowney Lane
Billings, Montana 59101
IV-D-42 Dean C. Marriott, Commissioner
State of Maine
Department of Environmental
Protection
State House Station 17
Augusta, Maine 04333
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TABLE 1. LIST OF CQMMENTERS (CONTINUED)
Docket Number A-84-49
Docket Item Number Commenter/Affiliation
IV-D-43 Harry H. Hovey, Director
Division of Air Resources
New York State Department of
Environmental Conservation
50 Wolf Road
Albany, New York 12233
IV-D-44 Ronald Cohen, President
Cohen & Peck, Inc.
14 Arrow Street
Cambridge, Massachusetts 02138
IV-D-45 Claren Lehman
Hitzer, Inc.
269 East Main Street
Berne, Indiana 46711
IV-D-46 Rod Weber, Product Sales Manager
The Will-Burt Company
169 South Main Street
Orrville, Ohio 44667
IV-D-47 John G. Meeker
Fire Glow Distributors, Inc.
Route 6
IV-D-48 Warren W. Tyler
State of Ohio
Post Office Box 1049
Columbus, Ohio 43266
IV-D-49 John G. Meeker
Fire Glow Distributors, Inc.
Route 6
Jefferson Valley, New York 10535
IV-D-50 David D. Doniger, Senior Attorney
Natural Resources Defense Council
1350 New York Avenue, N.W.
Washington, D.C. 20005
3-7
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TABLE 1. LIST OF COMMENTERS (CONTINUED)
Docket Number A-84-49
Docket Item Number Commenter/Affi1i ati on
IV-D-51 Don Wilkening
Wilkening Fireplace Home Heater
HCR 73 Box 625
Walker, Minnesota 56484
IV-D-56 Jay W. Shelton, President
Shelton Research, Inc.
1517 Pacheco Street
Santa Fe, New Mexico 87501
IV-D-57 Jay W. Shelton, President
Shelton Research, Inc.
1517 Pacheco Street
Santa Fe, New Mexico 87501
IV-D-58 Don Wilkening
Wilkening Fireplace Home Heater
HCR 73 Box 625
Walker, Minnesota 56484
IV-D-59 William Schmidly, President
Country Flame
Post Office Box 151
Mt. Vernon, Missouri 65712
IV-D-61 Quantek Products, Inc.
13500 High Point Drive
Traverse City, Michigan 49684
IV-D-64 Robert P. Dalley, Planning
Section Manager
State of Utah
Bureau of Air Quality
Post Office Box 16590
Salt Lake City, Utah 84116
3-8
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and appliance. According to this commenter, most woodsmoke is caused by
"problem burners" (i.e., users) who will continue to pollute no matter what
stove is purchased. The commenter believes opacity limits are more useful
than an NSPS. (IV-D-37)
Response: EPA agrees that there are many factors affecting emissions
from wood heaters including both stove design and consumer practices.
However, the primary factors are the restriction of combustion air and stove
design. Consumers have no control over stove design and their control of
combustion air is dictated by their heating needs and need for overnight
burns. The standards serve to control the design features (i.e., improving
combustion either catalytically or noncatalytically) through performance
testing, whereas consumer practices cannot be regulated through such a
program. However, the regulation requires that labels and owner's manuals
address operation and maintenance. The regulation prohibits consumers from
operating wood heaters contrary to the owner's manual.
EPA agrees that opacity limits may be useful for local law enforcement
efforts, but we are aware of no data relating opacity to best demonstrated
technology (BDT) --especially under actual conditions-- or to specific
emission limits, which represent the weighted average of test runs at four
different burn rates of a standardized test fuel.
1.3 Commenters IV-D-18 and 24.
Comment: One commenter stated that the use of BDT for the control of
pollutants from woodstoves is unnecessary in isolated locations and that the
requirements of the regulation should be exempted for households at a
distance of greater than one-half mile from the nearest dwelling or in areas
with an average dwelling spacing of one-quarter mile or less. (IV-D-18)
Another commenter agreed that the rule was unnecessary in rural areas.
(IV-D-24)
Response: Particulate matter emissions are pervasive and should be
controlled wherever they occur. In any event, it would be impossible to
administer and enforce a national standard that allows some mass-produced
consumer items to be used in some geographic areas while these same items
could not be used in other areas.
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Section 2. Opportunity for Public Comment.
2.1 Commenter IV-D-37.
Comment: One commenter said there were "no public hearings and no
opportunity for public comment or input until the final stages of the
rulemaking." (IV-D-37)
Response: Because of the way these standards directly affect the
public, EPA made an extraordinary effort to inform and involve the public in
the early stages of the rulemaking. In addition to the August 2, 1985,
Advance Notice of Proposed Rulemaking, EPA developed the proposed standards
using a regulatory negotiating committee. Representatives of all parties
affected by the regulation were given the opportunity to participate. This
was the first NSPS to be developed by regulatory negotiation. The general
public was invited to attend and was allowed opportunities to make
presentations and to comment from the floor during the committee's
deliberations. Notice of these meetings was provided in the Federal
Register and in trade journals.
There was also public comment at each of two National Air Pollution
Control Techniques Advisory Committee meetings on these standards. Notice
of these meetings was also published in the Federal Register. EPA technical
staff have been made available to respond by telephone and by mail to
interested members of the public and the news media. Finally, in proposing
these standards on February 18, 1987, in the Federal Register. EPA
specifically stated that a hearing would be held if requested. No requests
for a public hearing were received either by telephone or letter.
Approximately 60 public comment letters have been received by EPA. All have
been individually reviewed. Some of these comments have resulted in changes
to the final rule.
Section 3. Authority to Regulate.
3.1 Commenters IV-D-30 and 37.
Comment: Two commenters objected that EPA may not regulate wood
heaters as stationary sources under Section 111 of the Clean Air Act,
because woodstoves are mass-produced consumer products. (IV-D-30 and
IV-D-37)
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Response: EPA disagrees. Section lll(b)(l)(A) requires the
Administrator to maintain "a list of categories of stationary sources , . .
[which] in his judgment . . . caus[e], or contribute] significantly to, air
pollution which may reasonably be anticipated to endanger public health or
welfare." Section lll(a)(3) provides that "the term 'stationary source'
means any building, structure, facility, or installation which emits or may
emit any air pollutant." Section 111 requires the Administrator to
promulgate standards of performance for the sources within each category of
sources he has listed.
The definition of "stationary source"--"any building, structure,
facility or installation"--is broadly drawn. Congress left it to the
Administrator's judgment to apply the definition to particular air pollution
problems. "This definition is clearly designed to designate as facilities
those units of equipment—be they individual machines, combinations of
machines, or even entire plants—that the Agency finds to be appropriate
units for separate emission standards.11 Asarco,Inc. v. EPA, 578 F.2d 319,
324 n.17 (D.C. Cir. 1978) (emphasis added.) Nothing in the text or
legislative history of Section 111 suggests that a facility, such as a
woodstove, cannot be a stationary source because it is mass-produced or a
*
consumer product.
3.2 Commenter IV-D-30.
Comment: The commenter argued that the legislative history of the 1977
Amendments to the Clean Air Act shows that Congress intended that only large
industrial sources, such as power plants and steel mills, be regulated as
stationary sources under Section 111. (IV-D-30)
EPA listed woodstoves under Section 111 on February 18, 1987. (52 FR
5065). In so doing, the Agency explained its reasons for concluding that
woodstoves were a source category that met the criteria for listing under
Section 111.
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Response: EPA disagrees. The legislative history of Section 111 shows
that the purposes of that section are very broad—to "prevent the occurrence
anywhere in the United States of significant new air pollution problems,"
H.R. Rep. No. 1146, 91st Cong., 2d Sess. 3 (1970); National Asphalt Pavement
Ass'n v. Train. 539 F.2d 775, 783-785 (D.C. Cir. 1976); U.S. v. City of
Painesville. 644 F.2d 1186 (6th Cir. 1981). Neither is it true, as the
commenter argues, that EPA may regulate under Section 111 only those sources
that States attempt to lure by relaxing environmental standards. U.S. v.
City of Painesville. supra. 644 F.2d at 1192-1193.
Congress' addition of subsection (f) to Section 111 in 1977 shows that
Section 111 is not limited to large industrial sources. Subsection (f)
requires EPA to list categories of sources that are "major," (i.e., that
emit more than 100 tons per year of any pollutant. Section 302 (j). These
source categories include such small sources as stationary internal
combustion [gas or diesel] engines, 40 C.F.R. Section 60.16; 44 FR 43152
(July 23, 1979), and dry cleaning equipment, 40 C.F.R Section 60.16; Section
60.620. Moreover, Congress also specifically preserved EPA's authority to
list all categories of sources, no matter how small, that contribute
significantly to air pollution. Section lll(g)(2).
There is no support for the commenterJs argument that a stationary
source must be a building or something like a building. Asarco, supra, 578
F.2d at 324 n.17. Indeed, EPA has consistently interpreted the term
stationary source to include pieces of equipment, not merely buildings. See
Asarco. supra. 578 F.2d at 323; 40 C.F.R. Part 60, Subparts D-PPP. EPA's
interpretation of the term stationary source was well established by the
time Congress amended and reauthorized Section 111 in 1977. 40 C.F.R. Part
60, Subparts D-Z, AA, BB, HH. Congress' action therefore ratified EPA's
interpretation. United States v. Rutherford. 442 U.S. 544, 554 (1979).
3.3 Commenter IV-D-30.
Comment: The commenter stated that EPA had not conducted sufficient
rulemaking on the designation of woodstoves as stationary sources (but did
not explain why this rulemaking is insufficient). (IV-D-30)
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Response: EPA disagrees. This rulemaking has thoroughly considered
all the issues relevant to listing and regulating woodstoves under
Section 111.
3.4 Commenter IV-D-30.
Comment: The commenter also objected that EPA lacks authority to
promulgate the certification testing and labeling requirements in the
proposed rule. (IV-D-30)
Response: EPA disagrees. As EPA explained in the proposal, 52 FR
5013, col. 2, these requirements were proposed under Section 114 of the Act.
Section 114 provides:
(a) For the purpose...(ii) of determining whether any person is in
violation of any such standard [under, e....g., Section 111] ...or (iii)
carrying out any provision of this chapter . . .
(1) The Administrator may require any person who owns or operates
any emission source or who is subject to any requirement of this Act
... to (A) establish and maintain such records, (B) make such reports,
(C) install, use, and maintain such monitoring equipment or methods,
(D) sample such emissions (in accordance with such methods, at such
locations, at such intervals, and in such manner as the Administrator
shall prescribe), and (E) provide such other information, as he may
reasonably require.
The authority granted to EPA by Section 114 is quite broad. "[Ejection
114(a)(l) identifies a certain composite class of persons—those who own or
operate emission sources or who are subject to any requirement of the Act --
and authorizes the Administrator to require anyperson in that class to do
any or all of the five things enumerated." Ced*sInc. v. EPA, 745 F.2d
1092, 1098 (7th Cir. 1984) (emphasis added). "[T]he Agency is authorized to
request the owner or operator ... to supply the Agency with whatever
information it 'may reasonably require' to carry out its statutory
responsibilities." U.S. v. Tivian Laboratories. Inc.. 589 F.2d 49,53 (1st
Cir. 1978).
The certification and testing requirements of the final rule would
require manufacturers to test the emissions of woodstoves. A manufacturer
of woodstoves is a "person who owns . . . emission source[s]," and EPA may
therefore require him to test them. The test is, of course, for the purpose
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of determining whether persons who operate the stoves are in compliance with
the NSPS. The testing is therefore within the scope of Section 114.
The labeling requirements would require owners of stoves to attach to
the stoves labels that include information relevant to proper operation and
maintenance of the stoves, and relevant to compliance with the NSPS. EPA
believes that these labels are "records," "reports," and "other information"
within the meaning of Section 114(a)(l). EPA also believes that it is
reasonable to require stove owners to make this information available in the
form of labels attached to the stoves, because that will best ensure that
the information remains available to operators who must comply with the
NSPS.
Finally, Section 301(a) authorizes the Administrator "to prescribe such
regulations as are necessary to carry out his functions under this Act."
This is a broad grant of authority. E.I.duPontde Nemours & Co. v. Train,
430 U.S. 112, 132 (1977) (similar grant of authority under the Federal Water
Pollution Control Act); In re Permanent Surface Mining Regulation
Litigation, 653 F.2d 514 (D.C. Cir. 1981), cert, den. 454 U.S. 822 (1981)
(Surface Mining Control and Reclamation Act). EPA believes that to the
extent provisions of the rule are not authorized by Sections 111 and 114,
they are authorized by Section 301(a) as necessary to carry out the
functions authorized by Sections 111 and 114.
Section 4. Composition of the Regulatory Negotiation Committee.
4.1 Commenter IV-D-37.
Comment: One commenter questioned the validity of the regulatory
negotiation process contending that the committee was stacked in favor of
proponents of catalytic technology. The commenter also stated that none of
the committee members represented the retail segment of the industry.
(IV-D-37)
Response: In addition to the Wood Heating Alliance (WHA), which
represented both catalytic and noncatalytic wood heater manufacturers
(primarily the latter), there were three wood heater manufacturers
represented on the 16-member regulatory negotiating committee. Two of these
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three were manufacturers of noncatalytic wood heaters. The WHA also
represented the distributing and retailing segments of the wood heater
industry. EPA is not aware of organizations or groups specifically
representing noncatalytic manufacturers or retailers. No such organizations
or individuals responded to EPA's announcement of the formation of the.
regulatory negotiation committee. As a result of EPA's various efforts to
publicize the development of the rule and personal appearances by EPA staff
at industry association meetings, all segments of the industry were very
aware of the development of the rule and the negotiation. The planned
negotiation, its evolution, and the results were also highlighted in a
series of issues of Wood In Energy and Alternative Energy Retailer, industry
trade publications with wide circulation. Following completion of the
negotiation, a Federal Register notice summarizing the results was mailed to
over 1600 firms and individuals. The proposal was mailed to a like number.
Finally, the committee's selection of noncatalyst technology as BOT,
along with catalyst technology, is evidence that noncatalyst technology was
treated fairly by the committee.
Section 5. Pollutants Regulated.
5.1 Commenter IV-D-64.
Comment: A municipal health department and a State health agency
requested the Agency to consider including a carbon monoxide (CO) standard
in the woodstoves NSPS. The municipal agency pointed out that, according to
EPA figures, three of the five areas in the nation with the highest concen-
trations of CO have significant CO emissions from woodstoves. Further, as
compliance with the CO ambient air standards becomes a problem for other
localities, the impact from woodstoves will become more important. (IV-D-31)
The State agency noted that several areas are nonattainment for CO, and that
emissions from woodstoves are one of three major reasons for CO exceedances
in the winter. They said they understood that CO is reduced by PM controls,
but were concerned about not having a separate CO standard. {IV-D-64)
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Response: EPA considered regulating CO as well as PM, but rejected
this option. The addition of a CO limit would have unduly complicated
development of these standards and likely would have delayed implementation
for at least another year. The standards serve to increase combustion
efficiency, thereby significantly reducing both CO and PM--both of which are
the result of incomplete combustion. Based on the limited data available,
EPA does not believe that any benefits that may result from a separate CO
standard would outweigh the delayed implementation and complication that
would be associated with such a standard.
Section 6. Affected Facilities,
6.1 Commenters IV-D-12 and 28.
Comment: An association representing the pellet fuel industry
commented that the definition of "wood heater" seems to include wood-fired
pellet burners, but that the lack of a testing procedure seems to indicate
that it is excluded from the regulation. The association requests that EPA
either specifically exclude pellet burners, as it has furnaces, boilers, and
open fireplaces, or that a testing procedure be included in the regulation.
They stated that they were prepared to assist in the development of a test
procedure. The association noted that pellet burners are an example of BOT
since their emissions are 10 times lower than the Oregon DEQ Phase II
standard. According to the commenter, pellet burners now comprise less than
1 percent of the market, but their share will increase substantially in
future years. (IV-D-12)
Another commenter recommended that EPA clarify its intent regarding
pellet burners by describing in the test method the fuel and test procedure
for testing pellet burners. (IV-D-28)
Response: Pellet burners have very low emissions—typically lower than
the best controlled catalytic stoves. However, the committee decided to
cover these appliances because they are wood burning room heaters. Also,
for marketing and other reasons, many pellet burner manufacturers prefer to
be covered by the regulation. For pellet burners, as with any other
wood burning appliance, where there is a question as to whether the
appliance is covered by the regulation, EPA has the authority to require
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that the manufacturer have the appliance tested at an accredited laboratory
using Method 28A to determine minimum burn rates or air-to-fuel ratios.
The EPA has clarified Method 28 with respect to pellet burners by
incorporating testing procedures similar to those used by the Oregon DEQ
procedure with which pellet burner manufacturers are already familiar.
Because pellet burners use a continuously fed rather than a batch fed
process (and therefore are not characterized by a burn cycle), it is
unnecessary to require particulate sampling over a long period of time. The
certification test for pellet burners requires a two-hour test run at each
of the four burn rates. The only difference between the EPA procedure and
that used by Oregon is that EPA specifies fuel qualities in order to ensure
a greater degree of standardization. The pellet burner manufacturers
support this approach because it is not burdensome and yet puts them on an
equal footing with the conventional wood heaters with which they compete.
This procedure is included in the promulgated regulation under Section 6.7
of Method 28. For those appliances that may be fired by either cordwood or
pellets, the certification testing shall include both procedures.
6.2 Commenters IV-D-23, 28, and 56.
Comment: A State agency commented that the results of tests it had
conducted under contract showed that some appliances commonly considered
fireplaces would be "close to being considered stoves under the proposed
definition when tested according to EPA Method 28A." The agency suggested
these test data be examined closely before promulgation. (IV-D-23)
Referring to these same data, two other commenters recommended that in
order to provide an additional margin of safety (from misclassifying
fireplaces as wood heaters), the criteria should be relaxed by reducing the
air-to-fuel ratio from 35-to-l to 30-to-l and by reducing the minimum burn
rate criterion from 5 kg/hr to 4 kg/hr. (IV-D-28 and 56)
Response: EPA examined the data submitted by the State and alluded to
by the commenters. Rather than pointing out the need to change the criteria
for excluding appliances, these data show no instances where an appliance
that is generally regarded as a fireplace would be considered a wood heater.
There are four criteria by which a wood-fired appliance can be excluded
from the standards. By meeting any single criterion, the appliance can be
excluded, EPA believes this provides sufficient protection for manufactur-
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ers of appliances clearly intended to be excluded from the standards.
However, because there is a continuum of appliances which combine elements
of traditional fireplaces (i.e., oxygen-rich combustion and high burn rates)
with air-tight woodstoves, some appliances will be close to any objective
criteria established. Lowering the cutoff could provide a motivation for
some manufacturers of woodstoves to attempt to avoid applicability.
6.3 Commenter IV-Q-47.
Comment: A fireplace manufacturer proposed that fireplaces be
incorporated in the regulation as a separate category with different minimum
burn rate and fuel configuration requirements. The commenter stated that
the proposed regulation may have the effect of outlawing efficient
fireplaces. He said that "fireplace" should be defined to include inserts,
a freestanding, or a built-in device, and that the minimum burn rate should
be proportional to the size of the combustion chamber (perhaps 1 kg/hr for
each cubic foot of combustion chamber). (IV-Q-47)
Response: The criteria used to define "wood heater" will exclude what
are commonly regarded to be fireplaces. There may be instances where the
manufacturer calls his enclosed combustion air-controlled appliance a
"fireplace," when, in fact, the air-starved conditions in the firebox
resemble a woodstove. Test data indicate that the 35-to-l air-to-fuel ratio
or the minimum burn rate of 5 kg/hr excludes appliances commonly regarded as
fireplaces (see previous comment). The record shows that the NSPS reflects
BDT for all "wood heaters" as defined by the regulation.
6.4 Commenter IV-D-24.
Comment: One commenter said that an apparent loophole exists in EPA's
exclusion of fireplaces from the regulation. He cited the example of a
fireplace that is purchased by a consumer and is subsequently enclosed with
tight-fitting glass doors such that it meets the definition of "wood
heater," i.e., low air-to-fuel ratios, low burn rates, etc. (IV-D-24)
Response: Glass doors and other enclosures designed for masonry and
metal pre-fab fireplaces are popular accessories. Some of these have
combustion air controls. When added to a fireplace, they may have the
effect of creating the air-starved conditions and PM emissions that
characterize the appliances this regulation intends to control. The Agency
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has been contacted by one manufacturer of pre-fab fireplaces who believed
that his appliance, when fitted with glass doors sold as an accessory, would
meet the burn rate and air-to-fuel ratio criteria that define a "wood
heater" under this regulation. On the other hand, EPA believes that most
accessories of this type, especially when used with traditional masonry
fireplaces, are unable to achieve the degree of combustion air control
necessary to meet these criteria.
If a wood-burning appliance is designed to accommodate enclosures (or
vice versa) which may create air-starved conditions, EPA will require the
manufacturer to have it tested (i.e., Method 28A) with the enclosures in
place to determine if it is a facility affected by the regulation. If so,
the manufacturer would be liable for compliance. To do otherwise would
invite circumvention of the standards. For example, a woodstove
manufacturer could sell the stove and the stove door separately claiming the
latter to be an accessory.
The test of whether the appliance is designed to accommodate the
enclosure is based on the obvious intent of the manufacturer and the
physical characteristics of the appliance/enclosure combination. If a
manufacturer advertises or otherwise purports that the enclosure and the
appliance are mutually compatible or if a physical inspection indicates that
they are mutually compatible, EPA will require that the appliance be tested
with the enclosure in place according to Method 28A with the air controls,
if any, set at the lowest burn rate to determine if it is affected by the
regulation. "Mutually compatible" means that the enclosure can be attached
to a fireplace or woodstove in a manner that permits the appliance to be
air-tight or capable of being adjusted such that combustion air can be
controlled.
Where the fireplace manufacturer did not design his appliance for the
addition of accessories that create an enclosed firebox, EPA believes that
it may still be possible for such circumvention to occur. In such cases,
however, it would be the consumer rather than the fireplace manufacturer who
may be held accountable for making an affected facility. For example, if a
homeowner installs an enclosure on his new fireplace and if this enclosure
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results in the facility meeting the four criteria that define a "wood
heater," this homeowner has manufactured an affected facility. As noted
below, homemade or hand-built wood heaters are not exempted from this
regulation.
6.5 Commentars IV-D-18, 24, 27, 28, and 39.
Comment: One commenter stated that homemade woodstoves should be
exempted from this regulation because homemade woodstoves are used primarily
by the poor to provide inexpensive heat. (IV-D-18) Several other commenters
responded to EPA's request for comments on how to regulate kit stoves, the
most popular form of homemade woodstoves. (IV-D-24, 27, 28, and 39) These
commenters favored the regulation of these appliances because of the
relatively large number of such stoves, their impact on the environment, the
potential for future circumvention if they are not controlled, and the
potential sales that will be lost by manufacturers of wood heaters who have
incurred the additional expense of complying with the regulation.
Response: In response to the comment that homemade stoves should be
exempted because they provide inexpensive heat for the poor, EPA believes
that although the initial cost of a homemade stove may be less than a mass-
produced manufactured woodstove, because it is assembled by the homeowner
with some homeowner-supplied parts, it may likely be less durable and less
efficient—an of which may make it more expensive in the long run. Even if
homemade stoves were to have lower life cycle costs, the benefits of such
costs would not outweigh the environmental costs of exempting them from the
standards. Finally, it should be noted that for those who cannot afford the
upfront costs of a new certified wood heater, this regulation does not
restrict the sale of second hand stoves. The second hand stove market is a
major source of inexpensive wood heating appliances.
EPA agrees with the commenters who recommend that kit stoves be
regulated. One estimate indicates that homemade wood heaters comprise
5 percent of the market. Most of these are believed to be kit stoves. A
kit stove is a type of wood heater that someone other than the commercial
manufacturer completes or alters (in a way that would affect emissions) as
suggested by the manufacturer, A kit stove may or may not include all of
the components necessary to construct the appliance, but does include plans,
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designs, and assorted hardware (e.g., door, legs, flue pipe fittings).
Often, the consumer supplies a steel drum which becomes the firebox for the
stove.
EPA believes that the manufacturers of the kits should be subject to
the certification requirements as are the manufacturers of fully assembled
wood heaters. Therefore, EPA is requiring that kit manufacturers have their
designs certified. For those designs that are certified, the kit
manufacturer would include in the kit any necessary hardware for assembling
the emission controls (e.g., a catalytic combustor and associated equipment
such as flame impingement shields and a temperature monitoring port),
appropriate temporary and permanent labels, and the owner's manual.
Since much of the fabrication of the wood heater occurs at the retail
or consumer level, EPA requires that kit manufacturers submit a kit, rather
than a fully assembled wood heater to the accredited laboratory for
certification testing. To approximate more closely the quality of
fabrication that occurs among consumers, a laboratory technician, using only
the instructions and designs available in the kit, would construct a wood
heater using the materials in the kit and the type of firebox (e.g., size
and quality of steel drum) specified in the instructions. If the
instructions allow the consumer to substitute different components (e.g.,
different sized steel drums), each variation that could affect emissions
would constitute a different model and require separate certification.
EPA is aware of at least one manufacturer of wood heater kits who sells
catalytic combustors as an accessory. This same manufacturer has his stove
designs safety tested and provides labels indicating compliance with the
U.S. Consumer Product Safety Commission safety testing requirements.
Therefore, the approach described above would not represent a significant
departure from existing practice. As suggested in the proposal preamble, in
view of the emissions impact and the potential for circumvention if kit
stoves are exempted from this regulation, EPA believes it is reasonable that
kit stoves be covered by the regulation and that the manufacturers of the
kits be responsible for having their designs certified.
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6.6
Comment: A manufacturer who produces woodstoves designed primarily to
heat hot tubs advertised that his stoves may also be used to supplement home
heating and to preheat water going to a domestic water heater. EPA was
asked if these stoves are exempt from the regulation.
Response: These stoves generally are not exempt from the regulation.
The stoves are used to heat water in private hot tubs, which is a part of
domestic water heating. The stoves are also advertised as being able to
provide supplemental space heating and domestic water preheating. The
Administrator may exempt, on a case-by-case basis, hot tubs that exceed
800 kg, including water weight, if the stove could not be operated without
the water. For example, EPA is aware of a line of hot tubs heated by
woodstoves that, because of their aluminum construction, would melt if
operated outside without water. In this case, the water is considered an
integral part of the woodstove and, thus, the weight of the water could be
included as part of the weight of the woodstove for determining
applicability.
6.7 Coramenters IV-D-2 and 24.
Comment: A manufacturer of a masonry wood heater commented that
although he was exempted from the regulation because the weight of his
heater exceeded 800 kg., he was concerned that EPA might remove the
exemption. He argued that this exemption should not be removed because
fast-burn masonry wood heaters were inherently clean burning and were not
suitable for EPA test procedures because of their fast burn/controlled heat
output nature. He said that, should EPA decide to regulate these
appliances, the Agency should adopt a design standard approach such as one
being developed by the American Society for Testing and Materials (ASTM)
rather than a performance standard. (IV-D-2) Another commenter also asked
for clarification of the applicability of the standards to so-called
"Russian stoves" or "European tile stoves." (IV-D-24).
Response: The 800 kg cutoff was established as an easy means of
excluding the high-mass fast-burn wood-burning appliances sometimes known as
"Russian stoves" or "European tile stoves." These devices typically operate
at hot, fast burn rates and cannot easily be damped. It is also likely that
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they are incapable of meeting the 5 kg/hr minimum burn rate. The intent of
the regulatory negotiation committee was to eliminate the need for
laboratory testing to determine applicability of these appliances which rely
on relatively clean-burning air-rich conditions and which typically have
high combustion efficiencies. It should be noted, however, that the 800 kg
exclusion does not apply to an appliance sold separately from the masonry or
other materials which would cause it to exceed the 800 kg threshold.
6.8 Commenter IV-D-2.
Comment: The same commenter said that EPA should not only exempt
fast burn masonry wood heaters, but should also conduct research and
development testing as a means of encouraging these appliances as a clean
burning alternative to metal wood heaters. (IV-D-2)
Response: The standard promotes the development of all forms of
clean-burning wood-fired appliances and therefore does encourage the
appliances with the characteristics the commenter describes.
6.9 Commenter IV-D-28.
Comment: A manufacturer stated that the provision of the proposed
regulation exempting manufacturers of fewer than 2,000 stoves per year from
the regulation for 1 year will result in 30 percent of the woodstoves
produced in that year being uncontrolled. The manufacturer recommended that
this exemption be limited to manufacturers of fewer than 1,000 woodstoves
per year, estimating that this would leave only 10 percent of the woodstoves
manufactured during that period being uncontrolled. (IV-D-34) On the other
hand, a State regulatory agency supported the 1-year exemption as proposed,
saying it will provide market equity for small firms and reduce certifi-
cation time for large firms. (IV-D-48)
Response: The regulatory negotiation committee agreed to the 1-year
delay in applicability to manufacturers of fewer than 2,000 heaters per year
to bring into balance several considerations. First, small manufacturers
are less prepared to meet the new standards because most do not market their
products in the States which already have emission regulations for wood
heaters. Second, the research and development costs, the securing of
financing, and the capital costs of retooling are generally a greater burden
on small manufacturers than for large manufacturers. Third, the
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manufacturers of fewer than 2,000 heaters per year were estimated to account
for only about 10 percent of total woodstove market based on an EPA survey
of manufacturers. This suggests that the environmental impact of this delay
will be minimal. Only 2 percent of the wood heaters produced in the first 5
years of the standard would fall under this exemption. Fourth, by delaying
applicability for this segment of the industry (which is estimated to
account for 70 percent of the manufacturers), the accredited testing
laboratories and EPA's certification program would be better able to handle
the anticipated demand for testing and EPA certification application review.
Even with this delay in applicability, the committee was concerned that
there may be insufficient testing and application review capability to
handle the potentially large number of applicants for certification. In
summary, the 1-year delay for the small manufacturers (1) provides
additional time to comply for that segment of the industry for which meeting
the 1988 and 1990 deadlines would be most burdensome, (2) incurs minimal
environmental impact, and (3) relieves the testing and application review
process.
6.10
Comment: One commenter asked whether a company that produced fewer
than 2,000 stoves per year could purchase and produce a stove design from a
large manufacturer and still be entitled to the 1-year exemption as a small
manufacturer. This same commenter asked whether a qualifying small
manufacturer could produce his quota of uncertified stoves in addition to an
unlimited number of certified stoves.
Response: EPA recognizes that it is possible for a large manufacturer
to abuse this exemption by "farming out" production of woodstoves to several
qualifying small manufacturers. The intent of the 1-year exemption is to
give the small manufacturers, who presumably have fewer financial resources,
more time to develop a clean-burning model and become certified. The
exemption is designed for manufacturers who are not organizationally or
financially related to a larger corporate entity. EPA will evaluate, on a
case-by-case basis, claims for such exemptions taking into account whether
or not the small manufacturers rely on their own financial resources and
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ability to raise capital. In the case of a small manufacturer merely
purchasing the right to produce a stove design owned by a larger
manufacturer, the small manufacturer would be entitled to the 1-year
exemption.
In response to the second question, a small manufacturer may produce up
to his limit (i.e., not to exceed base year production) of uncertified
stoves in addition to an unlimited number of certified stoves.
6.11 Commenter IV-D-18.
Comment: One commenter stated that irrespective of the date of sale,
second-hand stoves should be exempt from any standard if they have been in
use for over one year. These stoves are most frequently used by low income
people. (IV-D-18)
Response: By way of clarification, it should be noted that once a wood
heater that is subject to the standard has been used by a noncommercial
owner (e.g., a homeowner) the only requirement affecting its resale is that
the permanent label be intact. The proposed regulation is being revised
slightly to clarify that the sale of a used wood heater covered by the
standard does not have to be accompanied by the temporary label or the
owner's manual. This revision pertains to sales by either commercial or
noncommercial owners.
6.12 Commenters IV-D-21 and 36.
Comment: Two manufacturers of wood-fired cookstoves requested an
exemption from the standards for these appliance types. (IV-D-21 and 36)
One manufacturer requested an exemption from the first phase of the
standards beginning July 1, 1988, but said that he believed his firm may be
able to design a cookstove that would be able to comply with the second
phase beginning July 1, 1990.
The manufacturers stated that the design principles for room heaters
and cookstoves were significantly different. One manufacturer said that the
principle behind the design of the combustion chamber for the cookstove is
to direct heat around an oven. He said that because they have complex
enveloping flue passages, cookstoves have different flow and draft
conditions from a space heater. He said that the use of catalytic
combustors on cookstoves is precluded because of the high drafts and high
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exit temperatures. He concluded by stating that he knew of no cookstove
capable of meeting the 1988 emission limits, (IV-D-21) The other
manufacturer said that a cookstove manufactured to meet the standards would
almost ensure the oven being useless, not being able to regulate oven
temperature in some extreme heat periods. (IV-D-36)
The cookstove manufacturers cited an additional reason for exempting
cookstoves from the standards. They said that cookstoves comprise a very
small fraction of the wood heater market. Estimates provided by the
manufacturers would place the cookstove share of the wood heater market at
less than 1 percent. (IV-D-21 and 36)
The manufacturers of cookstoves said that because genuine cookstoves
are distinct from space heaters, it would be easy to define a cookstove for
purposes of exempting them. One cookstove manufacturer also noted that the
Oregon DEQ had exempted cookstoves from its program and that the Canadian
government classifies cookstoves separately from other wood heaters.
(IV-D-21). The manufacturers said failure to exempt cookstoves could cause
manufacturers of wood-fired cookstoves to go out of business, thus causing
hardships for groups like the Amish, the Old Mennonites, and others without
natural gas or electricity. (IV-D-21 and 36)
One of the cookstove manufacturers observed that he would not qualify
for the small manufacturer exemption because he produces more than 2,000
other woodstoves per year. Under the proposed standard, he would be forced
out of the cookstove business until he could redesign his product, while
small manufacturers of cookstoves would be allowed to sell uncertified
cookstoves. (IV-0-21)
A manufacturers' trade association agreed with these comments and
recommended that in order to avoid potential abuse, cookstove manufacturers
or importers should apply for and obtain an exemption from EPA. To
accomplish this, they recommended that the final regulation include a
definition of cookstoves which focuses on the primary purpose of a
cookstove--the preparation of food for human consumption. The association
recommended that the definition list design features common to cookstoves
that EPA would consider in acting on an exemption request. These design
features would include:
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o An oven with an oven rack;
o A mechanism for measuring the temperature in the oven;
o A flame path which is routed around the oven;
o A shaker grate;
o An ash pan;
o An ash clean-out door below the oven; and
o The absence of a fan and/or heat channels to dissipate heat from the
appliance. (IV-D-28)
On the other hand, a state regulatory agency supported application of
the proposed standard to cookstoves because, in the commenter's opinion,
they are clearly capable of meeting the standards. (IV-D-48)
Response: The EPA agrees with the commenters who recommend excluding
cookstoves. The operational characteristics of cookstoves have not been
shown to be compatible with the BDT analyzed in this rulemaking. Also, the
number of cookstoves is very small relative to all the number of other wood
heaters. Therefore, the promulgated standard exempts cookstoves and
includes the definition of "cookstove" recommended by the industry trade
association with one modification: to qualify, the appliance must have a
minimum oven size of 1.0 cubic foot. This is smaller than the oven sizes of
bona fide cookstoves currently on the market, but large enough to discourage
circumvention of the standard by simply adding a small cavity and calling it
an oven,
6.13 Commenter IV-D-48.
Comment: One commenter recommended that coal-only stoves be regulated,
either under this standard or a separate standard. (IV-D-48)
Response: Coal-only stoves would have to be addressed under a separate
rulemaking because different operational characteristics, a different fuel,
different pollutants (e.g., SO-}, and different control techniques may be
involved.
6.14 Commenter IV-D-24.
Comment: A commenter asked if the standard applied to a wood heater
that is located outside and is designed to heat an entire house by means of
hot water lines or hot air ducts. (IV-D-24)
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Response: This unit would be considered a furnace or central heater
and would be excluded by the standard if it were tested and listed under
accepted American or Canadian safety testing codes or otherwise determined
by EPA. The principal difference between a furnace and other wood heaters
is that a furnace produces virtually all its heat as convective heat (rather
than radiant heat which is the principal form of heat from a fireplace and
most woodstoves) for distribution to enclosed living spaces. Usually
furnaces are larger than woodstoves and fireplace inserts and frequently
furnaces have forced air combustion. However, these two factors do not
always apply. The definition of furnace has been modified slightly in the
promulgated regulation to emphasize the convective/radiant distinction, and
therefore to discourage circumvection of this regulation by the marketing of
appliances which would otherwise be considered fireplace inserts or
woodstoves, but which are equipped to distribute heat to other rooms.
6.15 Commenter IV-D-18.
Comment: One commenter stated that wood-burning furnaces should be
regulated because these units produce creosote and cause chimney clogging.
The problem created by wood-burning furnaces is caused by over-sized fire
boxes that are operated under low-air conditions. Because furnaces are
already large and expensive, the commenter argues, the $200 additional cost
of control would still allow these units to be salable. (IV-D-18)
Response: The committee agreed that wood-fired furnaces should be
regulated, but emissions data were not available to set a standard. The
differences in technology and size between room heaters and furnaces and the
lack of emissions data on furnaces prevented them from being covered under
the same emission limits as other wood heaters. Because of this, the
regulation of furnaces and central heaters has been deferred by the Agency
so as not to delay implementation of this rule.
6.16 Commenter IV-D-33.
Comment: One manufacturer recommended that if residential furnaces and
boilers are required to be safety tested in order to be exempted from the
proposed regulations, this requirement be limited to residential units only,
and not apply to commercial or institutional furnaces and boilers. The
commenter recommended that only units below 180,000 Btu/hr output be
regulated. (IV-D-33)
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Response: Although this standard is referenced as pertaining to
residential wood heaters, the intent is to cover wood heaters of a certain
size range regardless of where they are located (e.g., offices, warehouses,
stores, as well as homes). It is possible that units greater than 180,000
Btu/hr may be exempted from the standard on the basis of either the 20 cubic
foot firebox size or the 5 kg/hr burn rate criteria. These tests may be
less burdensome than being safety tested and listed. The Agency does not
intend to exclude an appliance that is called a furnace but that has a
firebox less than 20 cubic feet, and can be operated at less than 5 kg
per hour. The Administrator, on a case-by-case basis, may exempt furnaces
and boilers that are not safety listed.
6.17 Commenter IV-D-25.
Comment: The proposed regulation requires that manufacturers of wood
heaters seeking an exemption under the Oregon grandfather provision be
certified by Oregon DEQ by January 1, 1988 [(Section 60.530(c)(l)]. Citing
delays ranging up to more than one year between application/test report
submission and DEQ certification, the commenter recommended that wood
heaters for which certification test reports had been submitted to (but
which were not necessarily certified by) Oregon DEQ by January 1, 1988, be
eligible for this exemption. The commenter believes this will relieve
tremendous uncertainty and pressure on all parties concerned. (IV-D-25)
Response: The intent of the committee in this provision was to
recognize and avoid duplication of effort by those manufacturers who had
already gone to the expense of meeting Oregon's requirements (i.e., those
who were certified or were being certified in late 1986 and early 1987).
Manufacturers who had not committed to the Oregon certification process by
early 1987 would not be faced with duplication of efforts because EPA and
Oregon now use the same test procedures. Also, EPA is now capable of
handling certification applications and several new laboratories are being
accredited for EPA certification testing.
6.18
Comment: A manufacturer asked if Oregon "grandfathered" stoves are
required to be emissions tested as part of the QA program and if Oregon
stoves are subject to Selective Enforcement Audits?
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Response: Oregon "grandfathered" stoves are exempt from the emission
limits contained in Section 60.532. EPA recognizes that there may be
differences between the test methods, and so an Oregon stove may be
"grandfathered" by EPA even though it may not have been able to pass an EPA
certification test. For this reason, emission testing as part of the
quality assurance or EPA enforcement audit programs would not be relevant
because there is no EPA standard with which to compare results. Oregon
"grandfathered" stoves are therefore not required to perform this part of
the QA program, although they are required to perform parameter inspections.
6.19 Commenter IV-D-34.
Comment: One manufacturer stated that the provision of the proposed
regulation allowing foreign woodstove manufacturers to import an unlimited
number of units into the United States prior to the July 1, 1988, Phase I
deadline in the proposed regulation would have a negative impact on U.S.
manufacturers and the nation's economy. The commenter expressed concern
that subsidized foreign manufacturers could import large numbers of
uncertified stoves into the country during that time and that this would
have an adverse effect on U.S. manufacturers, on the balance of trade, and
on air quality in the U.S. (IV-D-34)
Response: EPA's authority under Section 111 is limited to adopting
NSPS that reflect BDT. The only actions EPA could take to mitigate the
adverse effects alleged by the commenter would be to advance the effective
date of the NSPS or to reduce the 2-year time period that is allowed for
sale of existing inventories. But EPA believes that the July 1, 1988, date
properly reflects BDT and that at least a 2-year period for sale of existing
inventories is reasonable. Because woodstoves are a mass-produced product,
an earlier date would cause adverse economic impacts by disrupting current
model line production schedules. Similarly, a period of time shorter than
2 years to sell existing stocks could have serious economic impacts on
retailers, distributors, and manufacturers who may be unable to deplete all
of their existing inventory in less than 2 years. Furthermore, the alleged
adverse effects that might be prevented by an earlier date are purely
speculative and, in EPA's judgment, unlikely to occur for two reasons.
First, the committee concluded that the costs of maintaining large
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inventories and the uncertain demand for closed-out models would discourage
stockpiling of stoves built before the effective date. Second, EPA is not
aware why the opportunity to stockpile large numbers of stoves prior to
July 1, 1988, necessarily favors foreign manufacturers. Such an
"opportunity" would be available to both domestic and foreign manufacturers.
Section 7. Definitions.
7.1 Commenter IV-D-39.
Comment: One commenter noted that the proposed definitions of "boiler"
and "furnace" which require that boilers and furnaces be "tested and listed
as a boiler under accepted American or Canadian safety testing codes," would
place a "severe economic burden" on many boiler and furnace manufacturers
who would have to test and list solely to meet this provision because there
are large regions of the country where safety testing is not required for
such products. (IV-D-39)
Response: The purpose of requiring that boilers and furnaces be tested
and listed in order to be entitled to an exemption was to discourage
appliances which are not bona fide boilers and furnaces from claiming this
exemption. Manufacturers of bona fide boilers and furnaces that are not
safety tested and listed may apply to EPA for case-by-case consideration.
The request for exemption must be accompanied by supporting evidence to
support the claim and must be submitted to: Wood Heater Certification,
Stationary Source Compliance Division (EN 341) U.S. EPA, 401 M. Street SW,
Washington, D.C. 20460.
7.2 Commenter IV-D-27.
Comment: A laboratory spokesman asked if the term "accepted" in the
definitions of "boiler" and "furnace" meant safety testing codes "such as
ANSI/UL 391, Standard for Solid-Fuel and Combination-Fuel Central and
Supplementary Furnaces." (IV-D-27)
Response: The commenter is right. In addition to this code for
furnaces is the one for boilers CSA B366.1 (Canadian Standards Association).
7.3 Commenter IV-D-39.
Comment: A commenter asked for clarification concerning the phrase "an
opening for loading coal which is located near the top or side of the stove"
in the definition of "coal-only heater." (IV-D-39)
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Response: The purpose of the definition is to prevent circumvention.
EPA agrees that this criterion is ambiguous and therefore it has been
removed from the promulgated version of the regulation.
7.4 Coramenter IV-D-39.
Comment: A manufacturer of coal heaters wrote to describe stoker coal
heaters the commenter manufactures which do not meet all of the design
specifications in the proposed definition of "coal-only heater," but which
are intended to fire only coal. The commenter suggested that an additional
provision might be added to the definition of "coal-only heater" including
in the definition those coal-burning heaters that are stoker-fired.
(IV-D-46) Another comienter also contended that stoker-fed appliances could
not meet the requirement contained in the definition of "coal-only heater"
that they include "a grate or other similar devices for shaking or
disturbing the fuel bed." (IV-D-39)
Response: EPA agrees with the commenters and has revised the
promulgated regulation to allow a solid fuel appliance to be defined as
"coal only" if it has either a shaker grate (or similar devices) or a power
driven mechanical stoker. The appliance would also have to meet the other
criteria.
Section 8. Best Demonstrated Technology.
8.1 Catalytic.
8.1.1 Commenters IV-D-24 and 37.
Comment: Two commenters noted that operator practices greatly
influence the effectiveness of a catalytic woodstove. One commenter cited
such practices as burning colored newsprint, which can cause catalyst
plugging, and burning coal, which can "foul" a catalyst, as examples of poor
practices. (IV-D-24 and 37}
Response: EPA agrees with the commenter that operator practices may
influence the emission reduction capabilities of a catalytic combustor.
Catalysts, regardless of their application, theoretically have the potential
to be deactivated by sintering (partial welding or crusting on active sites)
or poisoning (blocking of active sites). For these reasons, the regulation
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requires that consumers be provided with specific information to encourage
good operating practices and to warn against misuse and requires consumers
to operate stoves consistent with the permanent label and the owner's
manual.
Available information from catalyst manufacturers indicates that
typically, less than 1 percent of their total sales are returned due to
inoperative combustors. EPA is unaware of any data demonstrating that
catalyst sintering occurs at temperatures common to wood heater
environments. EPA is aware of only one study that investigates catalytic
combustor poisoning. In that study, initial experiments showed that no
change in catalyst light off temperatures occurred as a result of burning
gift wrapping and chimney cleaning salts. Following the initial temperature
studies, the catalytic combustor was subjected to corrosive acid solutions
in an effort to block active catalytic sites. Subsequent emission tests
showed particulate levels approximately two times higher than levels
reported from an equivalent unpoisoned combustor in the same stove. The
catalytic combustor was then removed from the stove, soaked in an acid
solution containing metal salts, and retested. The measured emission level
was approximately the same as for the unpoisoned combustor. Results from
this study suggest that regeneration of active catalytic sites may occur
over a period of time. Results also demonstrated that with a fouled or
partially poisoned combustor, emissions were approximately one ninth the
levels reported for the same stove without a combustor. Finally, it should
be noted that consumers have an economic incentive to avoid practices that
would reduce the effectiveness of their catalytic combustors.
8.1.2 Commenter IV-D-18.
Comment: One commenter expressed concerns regarding the possibility
that catalytic converters might emit platinum into the atmosphere with the
flue gases. Therefore, the commenter recommended that the health and
welfare impacts of platinum emissions from catalytic converters be examined
and that the regulation of platinum as a pollutant be considered. The
commenter also suggested that the EPA set up a program for recycling the
platinum in catalytic converters so that these materials would not be
released to the water, groundwater, air, or soil. (IV-D-18)
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Response: EPA is unaware of any data that suggest that platinum, or
any of the other platinum group metals used in the production of catalytic
combustors, are emitted to the atmosphere. Studies addressing the longevity
of catalytic combustor performance shows that the emission reduction
characteristics of wood heater combustors are maintained for several
thousand heating hours. Similarly, automotive catalytic converters, which
also use platinum group metals, also demonstrate continued catalytic
effectiveness for several years. Results of both wood heater and automobile
catalyst longevity studies indirectly demonstrate that the noble metals that
perform the catalyst functions are not volatilized or emitted to the
atmosphere. This conclusion is consistent with the physical properties of
these platinum group metals (low vapor pressures at process temperatures,
and high melting temperatures) and with the definition of a catalyst - i.e.,
a substance that enhances the rate of a reaction without being appreciably
changed during the reaction. Furthermore, the presence of commercially
operated facilities for recycling noble metals from used automobile
catalysts is evidence that these platinum group metals are retained on the
substrate.
8.1.3 Commenter IV-D-37.
Comment: A commenter stated that the composition of the negotiation
committee and the proposed standard both reflect a bias toward catalytic
technology. The commenter questioned EPA's view that catalytic technology
represents best demonstrated technology for several reasons. First, the
commenter stated that catalytic stoves are no less dependent on operator
knowledge and experience for proper operation than are'noncatalytic stoves.
The commenter noted that field surveys in Oregon and other locales indicate
serious problems with the life, operation, and replacement of catalyst due
to improper operation and maintenance. Second, the commenter stated that
without the catalyst, a catalytic stove is dirtier than a noncatalytic stove
and, therefore, should be tested with the catalyst removed as well as in
place to ensure the standard can be met. This commenter contended that the
proposed standard promotes use of a catalyst as a substitute for good
design. Third, the commenter noted that many excellent noncatalytic stove
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designs are emerging, but that the proposed standard would discourage this
trend. Fourth, the commenter claimed that woodstove owners now burn
"brisker" fires in the evening and on weekends, a practice not appropriate
for catalytic stoves. (IV-D-37)
Response: With regard to the commenter's first point, EPA agrees that
both catalytic and noncatalytic stoves capable of meeting the standards will
require some operator knowledge and experience. With regard to the second
point, a catalytic stove with a catalyst in place has less emissions and
without the catalyst may have significantly more emissions than a
noncatalytic stove that meets the standard. Consistent with this, the
catalyst standard is about 40 percent more stringent than the noncatalytic
standard. Consumers have a great economic incentive to operate the stove
with the catalyst in place, since significant savings can be derived from
less wood used and less frequent chimney cleanings. Also, the regulation
provides for catalyst warranties, prohibits operation of the catalytic stove
without a catalyst, and requires language on the labels and in the owner's
manual warning against operating the wood heater with an inoperative
catalyst.
With regard to the third point, the committee explicitly addressed the
need to encourage technology by implementing a separate, less stringent
emission limit for noncatalytic stoves. Finally, the fourth point is
inconsistent with data available to EPA and the committee. No new data were
provided that would support this claim.
8.1.4 Commenter IV-D-30.
Comment: A retailer of noncatalytic stoves objected to the proposed
standards because they do not provide for an "emissions floor" for catalytic
woodstoves when they are used without the catalytic combustor or with a
catalyst which is ineffective. He stated that the assumption that consumers
will replace old catalysts when they are no longer effective has no basis in
fact. He suggested that the standard should require catalytic stoves to
meet certain emission limits even when the catalyst is ineffective or
removed. (IV-D-30)
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Response: The committee took into account the likelihood that some
consumers would fail to replace their catalytic combustors and that
emissions from new catalytic stoves could deteriorate over time. Data from
one survey were presented indicating that more than 90 percent of the owners
of catalytic stoves would intend to replace the combustors voluntarily.
However, these data may be optimistic because (1) the purchasers of
catalytic stoves were a biased population (because they voluntarily
purchased higher cost technology at a time when they were not required to do
so) and (2) there is often a discrepancy between what people claim they will
do and what they actually do—especially if there are costs involved. After
considering a variety of options for addressing the problem of catalyst
replacement and deterioration, the committee elected to (1) require the
two-year unconditional warranties, (2) include reminders and warnings on
labels and in owner's manuals to monitor catalyst performance and to replace
catalysts as necessary, (3) set a more stringent emission limit for
catalytic stoves that would offset possible degradation and lack of replace-
ment and would ensure the continuation of noncatalytic technology, and (4)
prohibit owners and operators of catalytic stoves from operating the stoves
without a catalyst.
EPA believes that another important element in catalyst performance is
public education. If the public is informed of the increased efficiencies
resulting from catalyst replacement, and the associated cost savings (less
fuel consumed and fewer chimney cleanings), the voluntary replacement of
catalysts would become an accepted practice for catalytic stove users.
8.1.5 Commenters IV-0-29 and 48.
Comment: Two commenters stated that certified woodstoves should be
required to be equipped with reliable temperature monitors to improve in-use
performance. Such a monitor would allow stove owners to maximize stove
operation and would be a tool which could be used by Agency inspectors in
identifying specific problems in stove operation and performance. The
commenter stated that installation of a catalyst temperature monitor would
be the most appropriate measure to include in the proposed standard.
(IV-D-29 and 48)
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Response: The committee considered requiring that all catalytic stoves
be equipped with a temperature monitor to assist the stove owner in
determining when the catalyst is functioning. However, there was concern
over the reliability and durability of these devices. Therefore, the
committee decided to require that the certified stoves only be equipped to
provide for a temperature monitor. EPA plans to require temperature
monitors when data become available indicating that monitors are available
at a reasonable price and that these monitors are accurate for periods
exceeding the two-year catalyst warranty. If data demonstrate that
temperature monitors are sufficiently reliable and available at reasonable
cost, EPA will propose that these devices be required on future catalytic
stoves.
8.1.6 Commenter IV-D-50.
Comment: One commenter recommended that EPA sponsor a competition to
foster development of temperature monitors. The "prize" would be a
"regulatory amendment which supplies the market to the successful product
designers." (IV-D-50)
Response: By stating that EPA will consider requiring temperature
monitors upon receipt of data demonstrating the durability and reliability
of these monitors at reasonable prices, EPA has essentially agreed with the
commenter. EPA will request comments on any proposal to require temperature
monitors—particularly on the estimated costs of the device relative to its
benefits and estimated lifetime.
8.1.7 Commenter IV-D-40.
Comment: One commenter pointed out that his company manufactures a
high temperature catalytic monitor which performs exactly as proposed by
EPA. (IV-D-40)
Response: The commenter did not provide data to support his claim. As
noted above, if the data show it to be appropriate, EPA will propose that
all future wood heaters be equipped with temperature monitors meeting
certain specifications.
8.1.8 Commenters IV-D-29 and 48.
Comment: Two commenters stated that owners of catalytic woodstoves
should be provided with incentives to encourage the timely replacement of
catalysts. These incentives might include: (!) providing a description of
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how to inspect a catalyst; (2) having retailers remind owners of the
catalyst's warranty and that it must be replaced if found to be inoperative;
(3) providing tax incentives to woodstove owners who replace their
catalysts; and (4) a requirement that warranty periods be increased in the
future. (IV-D-29 and 48)
Response: The owner's manual will provide information on how to
inspect a catalyst. A requirement that retailers remind stove owners of the
need to replace their catalysts is unenforceable. It is unnecessary, in
part, because it is in the retailer's interest to make such reminders
voluntarily. Also, EPA already requires this reminder on labels and in the
owner's manual. With regard to tax incentive programs, some local
governments have instituted tax incentive programs for the purchase of
clean-burning wood heaters. Nothing in the regulation prohibits this.
However, Section 111 of the Clean Air Act could not be used to require this.
With regard to the fourth point, the regulation accomplishes the
extension of warranties by requiring that the catalysts in wood heaters
produced after July 1, 1990 have three-year warranties against physical
degradation due to thermal shock.
8.1.9 Commenter IV-D-18.
Comment: One commenter suggested that the problem of catalyst
deterioration be met by adopting a program of free catalyst replacement,
financed by EPA. This approach would compensate for the adoption of a
standard requiring the installation of catalysts or other expensive controls
on woodstoves. (IV-D-18)
Response: A government-subsidized catalyst replacement program would
not be free. It would put the cost burden on taxpayers rather than the
woodstove owners who are responsible for controlling emissions and who are
benefiting from the increased efficiency from catalytic stoves.
8.1.10 Commenter IV-D-48.
Comment: A State regulatory agency recommended initiation of a
continuing research program for monitoring catalyst performance over the
lifetime of a stove. (IV-D-48)
Response: EPA has been and continues to evaluate both laboratory and
field studies of catalyst performance and degradation.
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8.2 Noncatalytic.
8.2.1 Commenters IV-D-37 and 43.
Comment: A State agency expressed support for the fostering of
noncatalytic technology through the establishment of separate emission
limits based on best demonstrated technology for this type of wood heater,
(IV-D-43) Conversely, a manufacturer of noncatalytic stoves believes that
the Reg Neg committee was biased against noncatalytic stoves because the
minimum burn rate requirement will make the standard difficult for
noncatalytic stoves to meet. (IV-D-37)
Response: While it is true that the low burn rate requirement is more
difficult for noncatalytic wood heaters to attain than for catalytic wood
heaters, as of October 1, 1987, there were 43 noncatalytic wood heaters
certified in Oregon that appear to meet the 1988 EPA emission limits and
minimum burn rate requirements. The minimum burn rate requirement is based
on data showing that homeowners primarily in New England, but also in
Oregon, averaged burn rates less than 1 kg/hr or less over a third of the
time the stove was operating. The data from the cold New England climate
would suggest that even lower burn rates may be selected by owners in many
areas.
8.2.2 Commenter IV-D-18.
Comment: Another commenter suggested that the solution to air
pollution from wood burning is to restrict the size of stove fireboxes to
encourage smaller fires using more air, rather than use of catalytic
devices. (IV-D-18)
Response: While reduced firebox size is one means of reducing
emissions, small fireboxes do not yield the high heat output and sustained
burns that many consumers desire. By specifying a performance standard
rather than dictating maximum firebox sizes, the manufacturer has greater
flexibility to achieve both consumer satisfaction and environmental goals.
Section lll(h) of the Clean Air Act permits EPA to set a design or equipment
standard instead of a performance standard only when "it is not feasible to
prescribe or enforce a standard of performance."
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Section 9. Format for the Standards.
9.1 Commenter IV-D-59.
Comment: One commenter asked why the standards were not based on the
amount of fuel consumed. (IV-D-59)
Response: The committee considered a variety of different formats for
the emission limit including one that would have limited PM emissions to
weight (i.e., grams) per weight of wood consumed (i.e., kilograms of wood).
The committee agreed to express the emission limits in grams per hour. It
is the least complex of the three formats, and it is consistent with current
regulations in Colorado and Oregon. Further, it provides more accurate
information than either of the other formats on actual particulate emission
rates.
Section 10. Certification Testing: General.
10.1 Commenters IV-D-9, 10, 11, 15, 16, 25, 35, and 59.
Comment: One commenter argued that the Oregon Method 41 (OM41) should
be allowed as a compliance test method for the wood heater regulation. The
commenter noted that the method meets Oregon equivalency criteria and data
available from independent studies demonstrate a "highly correlated
relationship with (Oregon) Method 7." Also, six commenters petitioned the
Agency to approve the use of OM41 for quality assurance testing noting that
the method is recognized in Oregon as equivalent to Oregon Method 7.
Additionally, manufacturers who have been using OM41 would have to discard
their equipment and purchase expensive new sampling equipment if OM41 is not
accepted. Comments raised in support of acceptance of OM41 are:
o A significant amount of data from simultaneous tests with OM41 and
Oregon Method 7 obtained by EPA, Oregon DEQ, and the manufacturers
verifies the high correlation between the results of the two
methods.
o The initial cost of implementing OM41 is half that of either
Method 5H or 56.
o OM41 uses short interval sampling and provides instantaneous
results, two factors which are valuable in diagnosis and
evaluation of wood heater design.
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o OH41 is easy to prepare, calibrate, and operate with limited
technical training.
o OM41 samplers have been calibrated by the manufacturer to produce
a standardized instrument for the industry, as opposed to the EPA
methods which must be calibrated frequently on site.
o OM41 equipment is compact and portable. The equipment can be
disassembled and reassembled repeatedly without loss of
reliability. This portability means that the equipment can be
used in the field to solve emission related problems. (JV-D-9, 10,
11, 15, 16, 25, 35, and 59}
Response: The test method is an integral part of any regulation and
the emission limit is related directly to the method. This is especially
true for particulate matter because particulate matter is not an absolute
quantity but rather is defined by the test method. The Agency recognizes
that the test method and the parameters specified for the method define the
amount and characteristics of the particulate sample collected and the
emission rate measured. Application of more than one test method to a
regulation needlessly complicates and may even result in unequal enforcement
of the standard. The regulatory negotiation process for the wood heater
regulation resulted in two test methods with a correlation factor for
comparability of the two methods' results. There was no suggestion or
support during the negotiations for the inclusion of OM41 as a third
compliance test method.
There are a number of technical deficiencies associated with the OM41
test method that make it unsuitable for a compliance test method. These
deficiencies are primarily in the area of quality assurance and quality
control of the data produced.
o The data reported in the literature comparing the OM41 results
with other test method results do not include many values in the
range expected for compliance testing of NSPS wood heaters (<10
g/hr).
o The OM41 sampling rate is not proportional to the flow rate in the
wood heater stack. Proportional sampling is necessary for
accurate measurement of wood heater particulate emissions.
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o The sample volume is not measured directly, but is calculated from
orifice readings. There is insufficient quality control on the
measurement of gas flow that is changing temperature, moisture
content, and other critical conditions making the flow rate
measurements imprecise.
o The stack gas flow rate is not determined using a carbon mass
balance approach as is used in the Oregon DEQ and the Method 5H
procedures. The OM41 method uses only the oxygen readings and
assumptions about the wood burn rate to calculate the stack gas
flow. In the technical papers mentioned by the commenter, the
comparisons of flow rate determinations using the OM41 approach
and the procedure in Method 5H show poor correlation.
o The dilution temperature in the OM41 sampler is dependent on the
temperature of the wood heater and, thus, is a variable. This
variability in filter temperatures will affect the filter's
collection efficiency of condensible wood heater emissions.
The wood heater manufacturers may continue to use OM41 for a number of
internal purposes. These include collection of interval emission samples
for diagnoses and for evaluation of designs, and sampling during field
evaluation. The OM41 method is not acceptable for internal quality
assurance tests for the same reasons cited above.
10.2 Commenter IV-D-18.
Comment: One commenter stated that the certification and testing
requirements of proposed regulation are too expensive for consumers, and
that alternatives should be considered based on smoke appearance and the
presence of a plume. (IV-D-18)
Response: Certification tests are required only once for each model
line and cover 5 years of production. Assuming that the costs of
certification testing are passed on to the consumer in the price of a
certified stove, EPA believes, these costs are reasonable. If, for example,
certification costs for a model line are $8,000 and if as few as 2,000
stoves per year are produced in this model line over 5 years, the per stove
cost to the consumer is less than one dollar.
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Although smoke appearance and opacity may be indicators of high
emissions, these techniques lack the precision of particulate sampling,
Moreover, smoke appearance and opacity testing would require the same
multi-burn standardized operating approach in order to fairly compare
performance among stoves across the burn cycle and at varying burn rates.
In short, emissions measurement is the only sure way of determining
compliance.
10.3 Commenters IV-D-37, 44, and 59.
Comment: Three commenters opposed the requirements that preclude fixed
leak technologies (i.e., nonair-tight stoves) and provisions that require
emission rates to be weighted more heavily in the low burn rate operating
condition, (IV-D-37, 44, and 59)
Response: The committee considered a variety of data relating to
actual homeowner wood-use practices in order to set the minimum burn rate
criteria and the weighting factors used to determine the composite emission
value. Data available to the committee based on actual measurements of wood
loaded into residential wood heaters in New England and the Pacific
Northwest showed that typical burn rates (even in the coldest winter periods
in New England) were about 1.2 kg/hr. The data also showed that the stoves
were frequently burned at rates less than 1 kg/hr. These new data were
consistent with earlier studies used by the states of Oregon and Colorado in
establishing their weighting schemes.
It is reasonable to expect woodstoves to be operated at low burn rates.
Because woodstoves do not typically circulate heat throughout the house, the
one or two rooms immediately around the stove may become uncomfortably warm
causing the users to reduce the burn rates. Also, during the transition
months of spring and fall heating demands vary--frequently requiring lower
burn rates.
Therefore, the regulation requires that stoves be tested at burn rates
of 1.25 kg/hr or lower in order to comply with the 1988 standard and 1.0
kg/hr or lower to meet the 1990 standard. Thus, the committee unanimously
agreed to the burn rate weightings in Method 28 that take into account the
full burn rate range, but emphasize the burn rates where the data show most
stoves operate.
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Consequently, Method 28 requires that woodstoves be damped using a flue
damper as necessary to achieve the required low burn rate. This criterion
is based on several considerations. First, as noted previously, studies
have shown that stoves are operated below these rates a high percentage of
the time. More broadly, however, it is important that current generation
air-tight wood heaters are generally high efficiency, high heat output
devices. At a burn rate of 1.0 to 1.5 kg/hr, the heat output will often
exceed the heating demands of many users due to the size of the space being
heated or to moderate outside temperatures. For this reason, homeowners are
motivated to reduce the burn rates as much as possible and it is reasonable
that they will use tight filtering dampers for this purpose. It is
reasonable, therefore, that the standards require affected facilities to be
tested at these low burn rates.
The situation is somewhat different in the case of appliances that
typically operate above 5 Kg/hr. These appliances are often designed with
aesthetics being a prime consideration. These appliances for example, often
have large glass doors for the aesthetics of an open fire. They also
typically exhibit characteristics of an open fire, such as high burn rates,
lower emission factors, and less frequent use, which are not intended to be
covered by these standards. These devices exhibit high minimum burn rates
primarily because of large fireboxes and/or leaky doors and gaskets. It
would be highly unlikely that a consumer would or even could slow the burn
rate significantly by adding a flue damper or other means to achieve the
desired low minimum burn rates less than 1.5 kg/hr to maintain a comfortable
temperature for several hours. The chance for circumvention of the
standards by modifying a device whose minimum burn rate is greater that
5 kg/hr is thus believed to be small.
However, these devices are also often installed with commercially
available flue dampers. For this reason, Method 28A requires the use of
commercially available flue dampers for applicability testing. In cases
where a specific damper is supplied with and is included in the cost of the
appliance, this damper may be used in the applicability test. The EPA
recognizes that such commercially available dampers are not necessarily air-
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tight and wants to make clear that air-tight dampers or other means beyond
commercially available dampers that would restrict the flue to the point of
smoke spillage from the stove are not required for Method 28A tests.
10.4 Commenters IV-D-39 and 41.
Comment: Two commenters contended that the Agency should specify test
procedures for pellet burning heaters and recommended the procedure
developed in the Oregon program. One commenter noted that this also applies
to stoker-fed appliances. According to the commenter, the test procedure
elements that must be addressed are fuel characteristics, flue dimensions
and materials, burn rates, burn duration, and use of alternative parameters,
such as CO, in lieu of particulate sampling. (IV-D-39 and 41)
Response: The Agency agrees with the commenter and has developed test
procedures for pellet-burning wood heaters. These appear in Section 6.7 of
Method 28.
10.5 Commenter IV-D-1.
Comment: One commenter believed that laboratory testing creates
artificially low draft conditions because the flue is discharged into the
laboratory space. The commenter stated that temperatures in the laboratory
are higher than the outdoor temperatures within home installations, creating
a totally different draft condition. One result of this, the commenter
reasoned, is that the wood heaters may have difficulty achieving the low
burn rates, or a manufacturer may make misleading air supply setting
indicators. The commenter also questioned the citing of the manufacturer's
burn rate on the temporary label but nowhere else. The commenter cited a
statement in Appendix I of the proposed regulation, "The low end of the burn
rate range indicated on the label should reflect the low end of the burn
rate achievable by the wood heater as sold and not as tested in the
laboratory." (IV-D-1)
Response: The commenter has misinterpreted the statement in
Appendix I. This section of the appendix refers only to wood heaters which
were subjected to artificial draft control measures in order to fall within
the required low burn rate category during the certification test. The
regulation does not require manufacturers to label or mark air supply
settings on wood heaters reflecting burn rates achieved during certification
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testing. The Agency agrees that the certification procedures do not
necessarily duplicate the in-home operation of a wood heater. This is
primarily because of the highly variable operating procedures used by wood
heater owners. The laboratory test procedures represent in-home conditions
as much as possible in a controlled, standardized environment. Such
laboratory standardization is necessary to ensure equal application of the
rule.
10.6 Commenter IV-D-56.
Comment: A commenter noted that burn rate categories in Method 28 are
incomplete. There is a gap between Categories 2 and 3. (IV-D-56)
Response: The commenter is correct. The lower limit for Category 3
should be 1.25 instead of 1.26 kg/hr so that a burn rate of 1.249 kg/hr is
in Category 2 and a burn rate of 1.250 is in Category 3. This has been
corrected in Method 28.
10.7 Commenter IV-D-29 and 46.
Comment: Two commenters stated that Phase I testing protocols should
be expanded. One said the protocol should include measurement of polycyclic
organic matter (POM) and respirable particulates, while the second urged
inclusion of carbon monoxide, visible emissions, stack temperature, and
combustion efficiency. They argued that this requirement could be used to
verify that the control of particulate matter results in adequate control of
other woodstove emissions, and could also contribute to improvement in
woodstove design and operation. (IV-D-29 and 46}
Response: The expansion of the test protocols to include some of the
items requested by the commenters is not necessary for compliance
determination and would raise testing costs. Some of the items, such as
carbon monoxide and stack temperatures, are routinely recorded as part of
Method 5H.
10.8 Commenter IV-D-1.
Comment: One commenter noted that the EPA testing procedure does not
measure methane and other unburned hydrocarbons (HC). He believes that
these can be "significantly high" from catalytic stoves which otherwise have
low particulate emissions. He suggested that the standard incorporate a
direct HC measurement using an afterburner test apparatus. (IV-D-1)
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Response: Since wood fuel is composed of cellulose and lignin (complex
organic materials), emissions generated from the combustion of wood are also
organic in nature (or composed of hydrocarbons). Although the test methods
specified by the regulation are not designed to quantify any specific
hydrocarbon, the solid and condensible materials collected in the sampling
trains and defined as particulate matter include a wide array of uncombusted
or partially combusted hydrocarbons. EPA has conducted wood heater emission
tests comparing the ranking of catalytic and noncatalytic stoves using the
promulgated Methods 5G and 5H and the state-of-the-art method for capturing
volatile and semi-volatile HC emissions (EPA Modified Method 5). The
results were that the rankings were unchanged. Therefore, EPA believes that
PM measurements using Methods 5G and 5H adequately reflect reductions of
unburned HC.
10.9 Commenter IV-D-25.
Comment: One commenter pointed out that the denominator of the
arithmetic equation in the example weighted average emission rate
calculation is in error and should read 1.791. (IV-D-25)
Response: This was a typographical error and has been corrected in the
final rule.
10.10 Commenter IV-D-30.
Comment: A commenter argued that the test methods specified in the
regulations have not been examined to determine the correlation between the
emissions measured with these methods and wood heater emissions performance
in the field. (IV-D-30)
Response: There are many parts of the test procedures that were
developed as a result of field experience and data from field use. For
example, the wood loads and burn rate categories specified represent the
mass per unit volume ratio and burn rates determined from several large
scale studies of in-home use of wood heaters. However, there are a large
number of variables that will affect performance in the field such as wood
type, moisture, load size, and operating procedures. It is expected that a
wood heater that meets the standard and that performs well in laboratory
tests will perform well in the field relative to a wood heater that showed
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high emissions in laboratory tests. This correlation will not be precise
from wood heater to wood heater or even for the same wood heater in
different houses or a different times.
In response to questions received after proposal from accredited
laboratories, a provision has been added clarifying the role of wood heater
manufacturers during certification testing. This provision limits
instructions by the wood heater manufacturer on wood heater operation to
written communications prior to the beginning of the certification test.
The only exception is for the manufacturer who observes that the test is
being improperly conducted. He may then notify in writing laboratory
personnel of the problems. All instructions and notifications relating to
the certification test shall be reported in the test documentation. Any
special instructions are to be consistent with operating instructions in the
owner's manual, exept to the extent that they address details of the
certification test (e.g., achieving specific burn rates) that would not be
relevant to homeowner operation. In other words, the wood heater should not
be operated during the certification test in a manner significantly
different from homeowner operation in order to increase the likelihood of
passing.
10.11 Commenters IV-D-28 and 59.
Comment: A woodstove manufacturer trade association noted that the
proposed regulation specifically envisions additional work on test method
issues in the future (e.g., development of a test method for optional
efficiency measurements and a program of annual proficiency testing for
accredited laboratories). The trade association added that it is looking
forward to working with EPA on test method development since accurate tests
are an important concern. (IV-D-28) Another commenter recommended that a
mandatory efficiency level be included because improvements in efficiency
will also result in improvements in emission levels. (IV-D-59)
Response: The EPA agrees with the commenter that the proposed
standards envisioned additional test method development work. The Agency is
currently reviewing an existing wood heater efficiency test method that has
been recommended by both the commenter and the Oregon Department of
Environmental Quality. Such efficiency testing, if approved by EPA, would
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only be optional because the Clean Air Act does not authorize EPA to
establish heat output efficiency standards for sources regulated under
Section 111. The Agency will continue to work with the commenter in
reviewing the merits of optional testing of wood heater efficiency.
The Agency is also in the process of developing the laboratory
proficiency program details for 1988 program participation which will be a
continuation of the program implemented over the past year. The proficiency
program measures the proficiency of accredited laboratories in conducting
Method 28, Method 5G, and Method 5H test procedures on wood heaters as part
of the certification process. In addition, EPA is collecting data to
evaluate the repeatability and reproducibility of certification test
results.
Section 11. Method 28.
11.1 Commenters IV-D-1, 24, 30, 37, 44, and 59.
Comment: There were several commenters who opposed various aspects of
Method 28, which specifies the fuel loading and operation of the wood heater
to be tested. In general, most commenters took exception to the
standardization imposed by Method 28 in test fuel type and crib design, and
in wood loading and heater operations (e.g., air supply adjustments and
manipulations). Some commenters said the standardized procedures do not
reflect actual home use (IV-D-24); that they discourage innovation in
general (IV-D-24), or in a particular design (IV-D-1); that dimensional
lumber with spacers is unrealistic (IV-D-44); that Douglas fir is an
inappropriate test fuel because it is not widely available across the
country (IV-D-37), not representative of fuels burned across the U.S.
(IV-D-59), and creates biases against noncatalytic stoves and small
fireboxes (IV-D-30); that the prescribed crib and wood type does not create
the kind of coal beds a particular model relies on for optimum emissions
(IV-D-44); that the limitations on fire tending are too restrictive and
affect design (IV-D-44).
Response: Comments regarding standardization can be responded to as
follows:
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o Standardized test methods are necessary to achieve objective
comparison among heaters and comparison of emission performance of
individual heaters to a specified regulatory limit.
o There is an almost infinite number of variables that affect
natural draft wood heaters. A standardized test method creates
the reproducible test conditions that are necessary for comparing
performance of one heater with another.
o There is a significant emissions data base that has been generated
using Method 28 (i.e., Oregon data base). These data are
sufficient, in EPA's judgment, to show that Method 28 is a
reasonably reliable test method. The development of the standard
using data based on other procedures might have delayed the air
quality benefits of the regulation by one or more years.
o A standardized woodstove testing approach is commonly practiced in
the industry for safety and efficiency measurements and the
concept of such an approach for emission testing was accepted by
all committee members.
o Available data on consumer wood loading practices indicate that
the standardized wood loading specified in Method 28 does
approximate average consumer wood load densities.
The general objections to Method 28 raised by commenters are: (1) it
does not reflect real world practices of consumers in the field; (2) it does
not result in reproducible test results; and (3) it does not allow for
innovative and unique designs.
In response to the comments that Method 28 does not reflect real world
practices, first it must be recognized that there is no single set of
consumer wood selection, wood loading, and heater operating practices.
There may be as many such practices as there are wood heaters in operation.
EPA recognizes that neither Method 28 nor any standardized method neces-
sarily reflects each individual loading. In actual use every loading is
different even for the same user.
The objective of standardization is to develop a reproducible set of
conditions that is well within the range of typical wood fuels, loading, and
operational practices. The procedures in Method 28 fall well within the
range of real world practices.
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Several commenters noted that despite the effort to create reproducible
test results, it cannot be demonstrated that Method 28 achieves this. In
response, it is noted that emissions from natural draft wood-burning heaters
are known to be affected by a number of variables including burn rates, air
settings, draft conditions, fuel characteristics, and fuel quantity and
loading arrangements. The extent to which changes in any one or in any
combination of these variables affect emission rates is unquantified.
Although data are limited, it was the general conclusion of the committee
that intralaboratory testing precision (i.e., reproducibility averaged over
four test runs) was reasonable—less than + 1 g/hr. This value takes into
account all elements of the system including run-to-run emission variability
and sampling imprecision. EPA is convinced that requiring reproducible test
conditions (such as fuel type and loading arrangements) minimizes testing
variables, contributes to higher quality test results, and ensures
confidence in emission data comparison.
Finally, in response to the comments that Method 28 discourages unique
and innovative designs, EPA is unaware of data that demonstrate that such a
standardized testing approach is unable to differentiate well-controlled
from poorly-controlled wood-burning heaters. EPA is convinced that
compliance determinations should be made on a common basis since factors
such as wood-loading, fuel species, and air supply settings are known to
affect emissions. Allowing each wood heater to be tested using unique
operating conditions and fuel types and arrangement would prohibit the
comparison of emissions data established for regulatory purposes.
This standard provides for use of alternative test procedures for truly
unique wood heater designs where fuel loading is atypical. To date,
however, EPA has identified one wood heater design that would involve unique
wood loading procedures (i.e., pellet burners).
11.2 Commenters IV-D-1, 13, and 58.
Comment: One commenter argued that the 5 minutes allowed in Method 28,
Section 6.4.1, for the wood heater door to remain open at the start of the
test run is insufficient. The commenter suggested that 10 minutes is more
realistic, and cited Appendix I of the regulation that states that the stove
operator is advised to operate the wood heater at a medium to high burn rate
for 10 minutes during refueling before making a final burn rate adjustment.
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A second commenter stated that his experience as a laboratory research
supervisor has shown that the amount of time the wood heater door is open
significantly affects the peak heat output rates occurring during a test
run. In addition, test result repeatability could be improved, the
commenter reasoned, if the time allowed for the door to remain open were
more closely defined. The commenter recommended 1 to 2 minutes instead of
5 minutes. A third commenter argued that the time allotted for opening the
wood heater door during the test should not be limited to one occasion, but
door opening and coal raking should be allowed or required any time the burn
rate falls below 0.1 Ib per 10-minute period. (IV-D-1, 13, and 58}
Response: The first commenter has taken a phrase out of context in the
reference to Appendix I. This section of the appendix is describing general
procedures for starting a fire in the wood heater from a cold stove or low
coal conditions. This is not a condition the stove is in at the start of
the certification test. For the certification test, the wood heater is at
the desired operating temperature at the start of the test run. It is
unnecessary under such testing conditions to allow the door to be open
longer than 5 minutes to load the fuel charge and ensure ignition of the
fuel.
The limit on the time for the door to be open at the beginning or
during a test run is necessary for testing standardization. The limit is
also consistent with the times allowed by the Oregon test method which was
the basis for the emissions data for setting the standard. The Agency
agrees with the second commenter that the opening of the wood heater door
has a significant effect on wood heater emissions. Indications from the
accredited laboratories are that the present procedures are sufficient for
the certification testing. The Agency will continue to review the
procedures on this particular issue and may revise the methods by rulemaking
at a later time.
11.3 Commenter IV-D-1.
Comment: One commenter claimed that the definition of secondary air
supply is biased against stoves which are "true gasifier/combustors," where
processes of pyrolysis/gasification, secondary combustion, and heat exchange
are separated. The commenter disagreed with the definition in the
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regulation that secondary air should be introduced into a separate mixing
chamber only. The commenter noted that this is contrary to sound combustion
practice where, for example, in large commercial solid fuel burners,
secondary air is introduced above the fuel charge. The commenter concluded
that the regulation should not dictate how much stove tending should be
allowed using a biased evaluation of design features. (IV-D-1)
Response: The commenter has misinterpreted the purpose of the
secondary air adjustment provision. The purpose of the limitations on the
adjustments allowed for the secondary air supply and other similar
restrictions in Method 28 is to limit the potential for test result
manipulation. The restrictions are not intended to inhibit wood heater
design. The secondary air supply check in Method 28 is designed to detect
significant changes in the wood heater's burn rate resulting from
adjustments to the secondary air supply. Such changes to the wood heater
burn rate during a certification test run can significantly affect the
emission rate determined for that run. The provisions in the method are
intended to prevent such potential circumvention of the emission standard.
The method provides three options to the manufacturer on the secondary
air supply adjustment permitted during the certification test: one, do not
adjust secondary air supply settings during the test; two, provide design
drawings showing that the secondary air mixing chamber is outside the
primary combustion chamber (firebox); or three, demonstrate that the effect
on the burn rate resulting from adjustments to the secondary supply is less
than 25 percent. These options provide sufficient operating latitude while
maintaining testing integrity and standardization.
11.4 Commenter IV-D-56.
Comment: One commenter asked whether stove surface temperatures should
be recorded and reported individually or may the average be recorded and
reported? (IV-D-56)
Response: Section 6.4.2 of Method 28 requires that wood heater
temperature measurements be recorded every 10 minutes. The IQ-minute
frequency serves as a quality check to identify, for example, if adjustments
were made to the air supply settings. While the average temperature is used
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for determining compliance with the specifications, it is necessary that
each individual temperature measurement be recorded at 10-minute intervals
during the 1-hour pretest period and during the test run.
11.5
Comment: A laboratory asked EPA to respond to a question regarding a
stove with multiple primary air inlets, and with more than one control.
Primary air can enter through the bottom or top of the stove. Emissions may
vary depending on where the primary air enters. The laboratory posed the
following questions: During the certification test, who decides where the
controls are to be set? The manufacturer? The lab? Must these
instructions be included in the owner's manual?
Response: Clear written instructions on how to set the controls must
be given to the lab by the manufacturer before the test starts. The lab
must note this in the test report and include a copy of the instructions in
the report. These instructions must also be included in the owner's manual
if they affect how a consumer is to set combustion air to achieve desired
heat outputs. The manufacturer need not include instructions in the owner's
manual which are intended only to help the lab achieve a specific burn rate.
11.6 Commenter IV-D-13.
Comment: One commenter agreed that the five-point calibration of the
platform scale is necessary, but said that some scales have a small mismatch
in their temperature compensation systems. The commenter has observed that
errors exceeding the 0.05 kg limit can occur because of uneven heating. The
commenter suggested that a check of the scale calibration be required over
the operating temperature range. (IV-D-13)
Response: Absolute accuracy of the platform scale data is not critical
to the emission results since it is the difference between two values (at
about the same temperature) that is measured. The five-point calibration
ensures linearity of the scale output and is required periodically in the
method; however, an error or shift in the scale output curve as a result of
a temperature change will not affect the measurement difference between two
readings. The one-point check required for each certification test and the
periodic calibrations are sufficient for this purpose.
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11.7 Commenter IV-D-1.
Comment: A commenter noted the positioning of the wood heater and test
facility temperature monitors and the intended use of the measurements need
clarification. The commenter referenced Section 6.2.2 of Method 28 which
instructs the testing personnel to "position the monitor sensing tip on the
firebox exterior surface inside of any heat shield, air circulation walls,
etc." without describing what "etc." could be. The commenter suggested that
there are other terms that require better definitions, such as, insulation,
interior combustion, air preheater shell, and the phrase "the intent of the
descriptions above." The commenter also argued that the test facility
temperature monitor does not necessarily measure the test facility
temperature since it has a variable location relative to the wood heater air
intake openings. (IV-D-1)
Response: The Agency agrees with the commenter that some of the
wording and descriptions in this section of Method 28 need clarification.
The Agency has made clarifications. The commenter has misunderstood the
purpose of the test facility temperature measurement. The test facility
temperature, that of the air entering the wood heater, is recorded as an
indication that the conditions around the wood heater are within acceptable
limits. This temperature is not necessarily representative of the entire
test facility temperature.
11.8 Commenter IV-D-56.
Comment: One commenter contended that frequency of test facility
velocity measurements and the precision required for the measurements are
excessive. The commenter pointed to the treatment of auxiliary air blowers
in Method 28 as an indication that higher air velocities would increase
emissions from wood heaters. The commenter's recommendation was to require
measurement of test facility air velocity once per certification test. The
commenter continued that the requirement to conduct a pitot traverse before
each test run is excessive. The commenter believed that the calibration
factor over a series of five to ten test runs changes only a few percent and
recommended reducing the dilution tunnel velocity calibration to once per
certification test or every eight test runs, whichever is more frequent.
The commenter also suggested that the frequency of dry gas meter calibration
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checks-should be reduced from once each test to semi annually, when dual
trains are used. The commenter believed that the dual train approach allows
a check of the entire sampling system through the comparison of results
limit specified in Method 5G. (IV-D-56)
Response: The Agency believes that the frequency for room air velocity
measurements is not excessive for compliance testing. The procedures call
for the air velocity check to be conducted once before and once following
each test run. This air velocity check requires less than 1 minute to
complete. Additionally, the Agency believes that calibration of the
velocity measurement device semiannually is not excessive. The Agency
has relaxed the response requirements for velocity measurement devices so
that less expensive indicators may be used.
The Agency believes that the 10 to 20 minutes required to conduct a
pitot traverse during the pretest period of each test run is not excessive.
The documentation of the dilution tunnel flow rate for each test run is as
important as the particulate concentration measurement in determining
compliance for the wood heater.
In the same light, the calibration checks of the dry gas meters
following each certification test are necessary documentation of compliance
results. Note that the certification test report represents the only
documentation of compliance determination for each wood heater model. Such
documentation must be complete and contain all the quality assurance data
necessary for the protection of both the manufacturer and the regulator.
11.9 Commenter IV-D-25,
Comment.* One commenter proposed that the allowable upper bound
temperature for the test facility be increased from 90 to 100 degrees F.
The test facility temperatures, the commenter noted, can often exceed 90
degrees between May and September, and air conditioning costs for a test
facility over 20 feet tall can be excessive. The commenter also said that
the barometric pressure limit of 30.5 in. Hg should apply only to those test
facilities that artificially produce higher barometric pressure conditions.
(IV-D-25)
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Response: The test facility temperature limits represent the
conditions required for the Oregon DEQ certification tests. The data from
these tests are the basis for the standard. The Agency has no data that
would show what, if any, effect a higher test facility temperature may
produce. There is no basis for changing this temperature in the absence of
such data. The maximum facility pressure limit was meant to apply only to
pressurized testing tanks. The Agency agrees that it is reasonable to apply
this pressure limit only to artificially induced pressure situations. The
restriction in the method has been reworded.
11.10 Commenter IV-D-26.
Comment: One commenter stated that the Method 28 procedure for
determining the effect of secondary air supply adjustments on the wood
heater burn rate is different from the procedure used by the Oregon DEQ.
The commenter emphasized that the intent of this procedure is to distinguish
between primary and secondary air supplies in order to establish what air
supply adjustments are permitted once the test run has begun. The commenter
believed that the procedure in Method 28, which has not been tested in the
laboratory, is deficient, and its use may allow manufacturer manipulation of
burn rates during the tests and, thus, emission rates. (IV-D-26)
Response: The Agency agrees that the regulation's Method 28 procedure
differs from the Oregon DEQ procedure for the determination of the effects
of secondary air adjustment. In essence, the Oregon DEQ procedure requires
the direct comparison of the burn rates achieved on two separate test runs
with the secondary air supply adjusted during one run and not on the other.
The procedure in Method 28 compares the changes in burn rates measured over
several 20-minute periods during a single test run before and after repeated
changes in the secondary air supply setting. The purpose of both procedures
is the same, that is, to distinguish between a secondary air supply and a
primary air supply that affects burn rate significantly. The Agency
believes, after reviewing burn rate data from certification tests and
proficiency tests conducted under controlled laboratory conditions, that
precise repetition of a burn rate for a wood heater using the same
operational settings on successive runs is unlikely to occur. Differences
of over 25 percent at even the low burn rates are not uncommon. It is
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apparent that determination of the effects of secondary air supply
adjustments on burn rate could not be done reliably from the results of two
separate test runs. This is the reason that the Agency developed a
different approach to this question.
11.11 Commenter IV-D-26.
Comment: One commenter preferred that Method 28, Section 6.1, should
require the accredited laboratories to conduct the catalyst aging procedure
rather than allow the manufacturers to conduct the aging procedure. The
commenter believes this is important because an independent lab is a
disinterested third party. The commenter continued that if the manufacturer
is allowed to conduct the aging procedure, he should be required to record
and report hourly temperatures and temperature monitor locations both
upstream and downstream of the catalyst. There should also be a
specification for minimum temperature differential across the catalyst for
the required time period according to the commenter. (IV-D-26)
Response: The agency has revised this section of the method to clarify
that the wood heater aging prior to certification testing be performed by
the accredited testing laboratories.
There are several reasons for this. One is that it provides greater
assurance that the aging requirement is correctly understood and properly
performed and documented. Also, it allows the laboratory to gain experience
with the stove and to identify any problems that may have occurred in
shipping or otherwise, and that could interfere with successful completion
of the test. This will result in cost savings to manufacturers since the
50-hour aging costs only about $250, compared to the $1,000 to $2,000 cost
of single certification test runs. It will also reduce potential testing
delays and log jams because aging does not tie up the emission test
facilities. Finally, this will provide greater flexibility by allowing the
lab to plan for and to age several catalysts in advance and to have them
available as spares in case a catalyst is accidently dropped or damaged.
The Agency agrees that documentation of hourly temperatures over the
aging period should be included in the procedure and the procedure has been
revised to reflect this improvement. The Agency is not requiring the
monitoring of temperatures both upstream and downstream of the catalyst or
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to set a minimum temperature difference specification. The temperature
difference across the catalyst that indicates catalyst ignition is not well
defined. In addition, this value is not the same for all catalyst models
and brands. The Agency will continue to review catalyst temperature data as
they become available in an effort to establish a clear definition of
catalyst operating characteristics, but is not adding this specification at
this time.
11.12 Coimenters IV-D-25 and 26.
Comment: Two commenters asked for further clarification on determining
firebox volumes. At issue is the definition of firebox height on stoves
with arched fuel loading doors and openings. One commenter said that in
such cases, height should be measured as a horizontal line parallel to the
floor of the stove extending up to two inches above the top of the charge
door; the other suggested that the top of the box should follow a curve
parallel to the arch. (IV-D-25 and 26)
Response: EPA agrees with the first commenter. For arched or
irregular shaped door tops, a horizontal line two inches above the highest
point in the opening should be used to delineate firebox height.
11.13 Commenters IV-D-41 and 57.
Comment: One commenter felt that EPA should allow flexibility in the
location of spacers that are attached to test fuel pieces. He stated that
placement of spacers at the end of test fuel pieces in some cases promotes
"bridging," a condition in which burning occurs in the middle of fuel pieces
but does not extend to the ends. Bridging results in premature fire outage,
leaving unburned spacers and fuel pieces and causing emission test runs to
be aborted. The commenter recommended that EPA allow spacers to be placed
more centrally on the fuel piece, at locations up to 1/3 of a log length
from the ends. He stated that this spacer placement would prevent bridging
and allow normal collapsing of the fuel load, The same commenter
recommended that requirements for top-most spacers on the top layer of the
test fuel crib be removed from the method, because of the resulting
difficulties in loading some stoves. (IV-D-57)
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Another commenter stated that, in his opinion, test fuel crib arrange-
ments that require a single, odd fuel piece (such as illustrated in
Figure 28-2 shown in the proposed Method 28) should be stacked in the center
of the load. The commenter supports this symmetrical arrangement since he
feels that it more closely approximates real world use. This commenter also
agreed with the requirement that grade C or better lumber be used during
certification tests, but recommended that lower grade lumber be allowed
during pretest burns. (IV-D-41)
Response: EPA believes that moving the spacers or fuel pieces may
affect air flow and combustion characteristics and therefore emissions.
This could result in a change in the stringency of the regulation. The fact
that over 100 Oregon certification tests have been conducted using the
existing protocol suggests that this protocol is workable as now written.
Although the fuel quality of the pretest burn may not be as critical as the
test burn, there may be an effect and EPA believes that changing the
specifications is inappropriate.
11.14 Commenter IV-D-56.
Comment: Another commenter objected to the requirement that test fuel
may not be kiln dried. The commenter stated that he is unaware of data
supporting this restriction. He recommended that kiln-dried lumber be
permitted unless data exist that demonstrate that such fuel would yield
misleading results. (IV-D-56)
Response: The data used to set the emission limits was based on the
use of air-dried rather than kiln-dried Douglas fir. A change in such a
fuel specification would have an unpredictable effect on emission results
and would be inappropriate for this promulgation.
11.15 Commenter IV-D-56.
Comment: One commenter objected to the stringent fuel and coal bed
adjustment prohibitions in Method 28. The commenter, a test laboratory
owner, recommended that fuel adjustments be allowed anytime the burn rate
falls below 0.1 Ib in a 10 minute interval. He noted that the Oregon DEQ
opposes such a recommendation since, in their opinion, if the fire goes out
prior to consumption of 60% of the test fuel, the heater is not reasonably
capable of operating at the air setting and burn rate attempted. The
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commenter disagrees with Oregon DEQ and instead attributes fire outages
during testing to the wide spacing between test fuel pieces and the required
location of the test fuel spacers (conditions that do not exist when burning
cordwood). The commenter pointed out that the advantages of allowing more
frequent fuel adjustment would be fewer aborted tests and reduced testing
costs. (IV-D-56)
Response: The certification test should be a measure of the
appliance's emission characteristics rather than a reflection of the fire
tending abilities of skilled laboratory technicians. EPA is not relaxing
this requirement because of the potential effect on the stringency of the
regulation.
11.16 Commenter IV-D-25.
Comment: One commenter suggested that the specifications for the
insulated stack in Method 28 require testing and listing according to UL
Standard 103HT, but that testing by Underwriters Laboratory is unnecessary.
(IV-D-25)
Response: The Agency agrees with this comment and has revised the
wording of the method to reflect this.
11.17 Commenter IV-D-26.
Comment: One commenter reasoned that a hydrocarbon factor for pellet
burning heaters must be developed for the calculation in Method 28A, Section
6.1, if pellet burning heaters are covered by the regulation. (IV-D-26)
Response: The Agency agrees with this comment and notes that a similar
hydrocarbon factor for pellet burning heaters is necessary if Method 5H is
used for emission testing. The new factor is 0.0080 and has been included
in Methods 5H and 28A.
Sections 12. Method 5G.
12.1 Commenter IV-D-43.
Comment: One commenter believed that the tracer gas analyzer
specifications are not sufficient to ensure measurements in the midrange of
the analyzer output. The commenter suggested that additional specifications
are necessary. (IV-D-43)
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Response: The commenter is correct that the desired responses for the
analyzers are in the middle to upper response range. Method 5H is written
so that this will occur in most cases. However, for maintaining proportion-
al sampling rates, strict adherence to this range limitation is not
critical. The present specifications are sufficient for detecting
significant flow rate changes and allow flexibility in selecting calibration
gases.
In addition, the flow rate of the stack gases from wood heaters changes
an order of magnitude over the course of a test run making it difficult to
preselect a span value that would ensure measurements in the midrange of the
analyzer output at all times.
12.2 Commenters IV-D-23, 27, 28, and 56. .
Comment: Several commenters contended that while Method SG allows the
use of either (a) 47-mm filters in a dual train configuration, or (b) a
100-mtn filter in a single train, the data received in support of the
standard using the dilution tunnel method were collected using the smaller
filters and dual trains. The commenters believed that the use of dual
trains has obvious technical advantages to the wood heater manufacturer,
test laboratory, and the regulatory agency.
One commenter noted that 100-mm filter holders are expensive and
difficult to obtain. The commenter also noted that confidence levels
increase with the use of dual trains over a single train result. Two
commenters recommended that dual trains be required for all wood heater
sampling or for none.
One commenter listed several reasons in support of the use of dual
trains with the smaller filters over other sampling configurations. These
are:
1. The larger tare weight of the 100-mm filter results in a smaller
particulate catch to filter weight ratio (signal to noise);
2. The larger filters have potentially seven times more hygroscopic-
related variation in weight when compared to the smaller filters;
3. Electrostatic effects are likely to create larger weight
distortions for 100-mm filters than for the smaller filters;
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4. Measurement of probe and filter holder catches is less accurate
for 100-mtn filter trains than for the smaller filter trains.
(IV-D-23, 27, 28, and 56)
Response: The IQQ-mm filters and associated sample flow rate were
determined appropriate for Method 5G in ensuring an acceptable minimum catch
(50 mg) at the level of the standard. Data from emissions tests conducted
for and by the Agency have shown that this amount is necessary to ensure
adequate precision of a particulate emission sample. The sample flow rate
for the 47-mm sample train cannot provide the same amounts for the same
emission rate. This smaller catch is the reason the Agency has required
dual trains for the smaller filter equipment and not for the larger trains.
The four issues raised by the commenters are addressed as follows (in
order):
1. The larger filter weight has little to do with the accuracy of the
measurement of the catch, provided the balance response remains
linear. Balances used for sample mass determinations in the
ranges discussed here are linear. However, the amounts of catch
associated with the use of the smaller filters are low enough to
cause concern about balance detectability limits. The data from
the proficiency tests conducted for the Agency indicate that the
masses collected with the smaller filters for several test runs by
different laboratories were less than 1.0 mg. A balance with a
detectability limit of 0.1 mg provides a result with a confidence
of + 10 percent. This analysis does not support the commenters'
contention that the measurements on smaller filters are more
accurate than those with the larger filters.
2. Hygroscopic effects are eliminated with the desiccation procedure
required in the method. Note that the catch on a larger filter
will also be 7 times the catch on a smaller filter given similar
sampling conditions.
3. Laboratories must be aware of electrostatic effects and deal with
them no matter the size of the filter.
4. See the response to number 1, above. The measurement of probe
catches for many, if not most, of the tests performed with the
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smaller filter trains in the proficiency demonstration tests
have indicated zero mass, whereas the catches with the larger
filter sampling trains have resulted in significant probe and
filter holder catch measurements. An implication is that the
catch on the probe of the smaller filter train may be significant,
but is below the sensitivity limit of the balance. The com-
menters' use of the term "signal to noise ratio" is misleading.
Because the balance sensitivity remains constant over the range of
sample weights discussed here, the expected absolute precision of
sample catch masses is constant. That is, the "noise" for sample
mass measurements for either train is the same. Thus, the "noise
factor" is actually less critical for the larger masses collected
in the larger filter trains than for the masses collected in the
smaller filter trains.
12.3 Commenter IV-D-56.
Comment: One commenter noted that Method 5G includes a procedure for
measuring the flow rate in the dilution tunnel that requires the measurement
of molecular weight of the exhaust gas. The commenter asked whether there
is an acceptable alternative to measurement of molecular weight; if so, a
clarification should be included in the method. (IV-D-56)
Response: The dilution tunnel exhaust gas dry molecular weight can be
assumed to be 29 for the determination of flow rate. The method has been
revised to clarify this point.
12.4 Commenters IV-D-25 and 26.
Comment: One coimenter argued that the schedule for determining
constant weight in Methods 5G and 5H is too rigid -saying that, especially
with the smaller filters, weight changes beyond the initial 24-hour
desiccation period are very small. The commenter's recommendation is that
the 2-hour period between weighings be revised to 24 hours, or that the
methods allow the use of sample weights determined before the completion of
the 24-hour desiccation period. Another commenter provided results that
indicate that wood heater emissions filter samples changed little or
immeasurably over 120 hours of desiccation. The commenter suggested that
only the dichloromethane extracts should be subject to the constant weight
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definition in the method. The commenter's recommendation is that all
samples be weighed to a difference of 0.5 nig, or 1 percent of the net
weight, for two consecutive weighings, but that the time for desiccation be
unspecified. (IV-D-25 and 26)
Response: EPA believes that it would be inappropriate to relax or
delete specifications for desiccating samples. It is true that incomplete
desiccation may cause only positive biases in the emission results; however,
avoidance of any potential biases is critical for a standard that includes
enforcement audits, as does the wood heater standard.
The Agency agrees with the second recommendation in principle, but has
revised the wording of the weighing specification differently. The revision
deletes the minimum desiccation period of 24 hours. In its place is a
requirement that samples be weighed to a difference of no more than 0.3 mg
or 1.0 percent of the net weight, whichever is greater, between two
weighings no less than 2 hours apart.
Section 13. Method 5H.
13.1
Comment: One commenter said that the requirements for checking
proportional sampling in Method 5H are too onerous and not necessary. Even
with highly experienced operators, the commenter has experienced failure
rates of 50 to 75 percent in trying to maintain the sampling rates within
proportionality limits. The commenter noted that most errors occur because
of operator fatigue after two hours, combined with meter reading difficul-
ties. In addition, the commenter argued that proportional sampling is not
necessary. The commenter supplied data from four test runs to support the
claim.
Response: Proportional sampling rates are necessary when the emission
flow rate and the emission concentration both change significantly and
independently during the course of the emission test. The data available to
the Agency show that these are characteristics of emissions from wood
heaters. These data, collected in support of the Oregon DEQ program
development, (Kowalczyk, et al., "Particulate Emissions from New Low
Emission Wood Stove Designs Measured by EPA Method V," Residential Solid
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Fuels, 1981 International Conference, June 1981) show that more than half of
the participate emissions occur during the first 20 percent of the burn
period. An analysis of this degree of change to the particulate
concentration and the stack gas flow rate shows that proportional sampling
is necessary in order to determine the correct emission rates. The
commenter's report contains data from four test runs, each performed with
two Method 5H sampling trains operating simultaneously. One train was
operated at proportional sampling rates at every test point, while the other
sampling train was operated with a few test points beyond the proportional-
ity specifications in the methods. These results do not support the 50 to
75 percent failure rates mentioned by the commenter, nor are these results
conclusive evidence that proportional sampling is not necessary.
Proportional sampling has been required for the Oregon DEQ test program
(the commenter is an Oregon-grandfathered lab). Checks of the maintenance
of proportional sampling were not included in the Oregon procedures, but
have been included in the Methods 56 and 5H. The proposed procedures also
included acceptability limits for proportionality rates. These limits have
been relaxed in the promulgated version of Method 5H in order to avoid
inordinate rejection of test run results while maintaining reasonably strict
proportionality requirements.
13.2 Commenter IV-D-25.
Comment: A commenter noted that several minor changes in Method 5H
have been communicated to the accredited laboratories by the Agency since
the proposal of the methods. The commenter suggested that Method 5H and the
other methods be reviewed in detail to ensure that the changes are incorpo-
rated correctly. The commenter listed revisions including the allowable
filter temperature range, the deletion of probe heating requirements, and
corrections to the proportional sampling calculations. (IV-D-25)
Response: The Agency agrees with the commenter about the incorporation
of these and other clarifications and corrections to the methods. The
methods have been corrected.
Section 14. Relationship of Methods 5G and SH.
14.1 Commenters IV-D-22, 25, and 43.
Comment: Several commenters noted that results collected simultaneous-
ly with Methods 56 and 5H will often not agree. The commenters argued that
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this disagreement is a function of the results correction factor and not of
the wood heater emissions characteristics. For this reason, the commenters
continued, the manufacturer should be allowed to select data from either
method for reporting. The commenters argued that the equation showing the
relationship between Method 56 and Method 5H is imprecise and needs
revision. One commenter believed that the data used in developing the
relationship showed that there is no consistent relationship, and the
equation should be considered only an interim compromise.
Another commenter argued that the supporting data for the equation were
produced by three different laboratories and showed that the relationship is
laboratory-specific. The commenter believed that the relationship should
not be applied generally, but that each laboratory should develop a
laboratory specific equation. (IV-D-22, 25, and 43)
Response: The correction factor for relating Method 5G results with
Method 5H results is based on numerous direct comparison test data from
several laboratories. The large quantity of data used for this
determination tends to mask the run-to-run imprecision inherent in the
results. It is likely that the results of the two methods for any one test
run or even of a series of four test runs will disagree. The Agency
requires the reporting of all the test data for a certification test. There
are at least two reasons for this. First, the potential for data
manipulation is avoided. Second, the average of all the test data, even if
collected with different test methods, provides a more accurate measure of
the emission rate than the average of either of the two data sets taken
separately. The Agency recognizes that the equation relating Methods 5G and
5H results represents an average relationship. The regulatory negotiation
committee also recognized that, as discussed in the preamble, the actual
relationship may not be constant between laboratories and may differ from
the relationship defined in the method. It was concluded that small
differences would not affect or bias the certification results. The
advantages of allowing the use of both methods outweigh any small gain in
consistency that may result from the selection of only one method. Unless a
clear basis is found for revising the equation used to relate the results of
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the two methods (e.g., errors in the original data base or in the procedures
used by the laboratories supplying the data), the Agency does not anticipate
that the equation will be revised.
14.2 Commenters IV-D-25 and 26,
Comment: One commenter stated that Section 6.6 of Method 28 needs
additional wording on simultaneous emission sampling with two different test
methods. The commenter reasoned that the revision is necessary to prohibit
data manipulation of the certification test results. Another commenter
recommended that when simultaneous sampling is conducted, the manufacturer
should be allowed to select the data to be reported. (IV-D-25 and 26)
Response: The Agency agrees that the simultaneous operation of
sampling trains (same or different sampling methods) during certification
testing is allowed; however, all data from these tests shall be reported.
Results from all trains used for each valid test run shall be averaged, and
the average result for each test run is used in calculating the weighted
average. The average result for each test run must be below the applicable
cap unless the run is replaced as specified in the method. The manufacturer
may use either sampling method for internal quality assurance auditing;
however, the manufacturer will be liable for compliance auditing using
either method.
A related issue is that of sequential test runs conducted with
different sampling methods during the same certification test. This is also
allowed with the result for each test run being used to calculate the
weighted average. The result of each test run must be below the applicable
cap for compliance, and a test run result may be deleted only through
replacement with two or more test run results collected with the same
sampling method. The requirements for quality assurance and audit testing
remain as described above.
Section 15. Altitude Effects.
15.1 Commenter IV-D-23.
Comment.* One State agency requested that EPA develop information on
the performance of woodstoves at high altitudes. (IV-D-43) Another State
agency commented that the discussion in the preamble on altitude effects on
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emissions indicated that the issue was unresolved. They stated that this
issue was of "vital importance" in many western communities attempting to
develop PM-10 and carbon monoxide SIP strategies. The State urged EPA to
use existing test facilities to resolve this question. (IV-D-23)
Response: EPA agrees that the development of data on the performance
of woodstoves at high altitudes would be useful; however, the absence of
these data does not affect the present regulation. The data now available
are sufficient for EPA to conclude that this standard reflects BDT. EPA
will consider supporting such data-gathering and analyses consistent with
budget limitations and other program priorities (such as control of
furnaces, fireplaces, and retrofit controls on existing wood-fired
appliances).
15.2 Commenters IV-D-41 and 56.
Comment: One commenter believes that the altitude correction factor
allowed for manufacturer in-house emission testing is grossly incorrect.
Based on his experience of testing the same stoves at two different
altitudes using the same personnel and equipment he believes that the
current altitude correction factor is off by a factor of between 1/2 and 1/3
for catalytic heaters (i.e., corrected emissions rates are lower than
actual). On the other hand, the commenter felt that the altitude effects on
emission from noncatalytic heaters were difficult to quantify. Emission
effects attributable to preburn conditions and initial fuel and air supply
adjustments, in the opinion of the commenter, may far overshadow any
altitude effect. (IV-D-41) Another commenter expressed concern about the
lack of an altitude adjustment factor and the possibility of discrepancies
in appliance performance between low and high altitude locations. (IV-D-56)
Response: EPA agrees with the commenters that the effect of altitude
is uncertain and may be variable. This was the reason the committee agreed
not to allow an altitude factor to be used in certification testing. The
altitude factor was allowed only for in-house emission audits. These tests
are less critical than certification tests and their cost outweighs concerns
regarding the imprecision of the altitude factor. As further data become
available, EPA will consider revising this factor.
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Section 16. Laboratory Accreditation.
16.1 Commenters 1V-D-7, 25, 28, and 41.
Comment: Four commenters were concerned about the duplication of
laboratory accreditation functions by the Agency and the National Voluntary
Laboratory Accreditation Program (NVLAP). Because NVLAP has limited
emission testing experience and the NVLAP fees increase the costs of
business unnecessarily, the commenters recommended the requirement for NVLAP
accreditation be deleted from the regulation. One commenter noted that
original support for including NVLAP accreditation was based on a concern
about numerous, potentially divergent State and local accreditation programs
for accrediting emission testing laboratories. The commenter observed that
the performance of the Agency's testing laboratory accreditation program to
date has made it clear that a NVLAP accreditation, as a precondition to EPA
accreditation, is unnecessary. (IV-D-7, 25, 28, and 41)
Response: The Agency agrees with these commenters and has revised the
regulation to delete the requirement for NVLAP accreditation as a condition
for EPA accreditation.
16.2 Commenter IV-D-48.
Comment: A State regulatory agency stressed the importance of the
national laboratory accreditation program to "quality-assured, uniform
program administration." They recommended establishment of a renewal
accreditation schedule and procedures for certification revocation.
(IV-D-48)
Response: The regulation already includes provisions for renewal and
revocation of both laboratory accreditation and wood heater certificates.
16.3 Commenters IV-D-13 and 17.
Comment: A supervisor of a laboratory located overseas noted that
Section 60.535(b)(6) of the proposed regulation would allow only
laboratories located in the continental U.S. to be eligible for
accreditation. He said that although he understands the practical reasons
for this, he hoped that in the future there would be some form of
recognition of foreign accreditation programs. (IV-D-13) Also, a trade
official with the New Zealand embassy said that this requirement (no
accreditation outside the continental U. S.) constitutes a "technical
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barrier to trade, since it provides considerable advantages to manufactur-
ers" located in the U.S. The official referred to Section 5.2 of the
General Agreement on Tariffs and Trade which provides that "whenever
possible" governments (party to the agreement) would accept test results and
certificates of conformity issued by relevant agencies in the territories of
other parties. He said that since NVLAP and the Testing Laboratory
Registration Council of his country had made progress in developing mutual
recognition and since NVLAP accreditation was required in the proposed rule,
the rule should include procedures whereby foreign laboratories can be
accredited as acceptable. (IV-D-17)
Response: Given the limitation of funds for EPA laboratory accredita-
tion and test observations, it is not possible at this time to extend
accreditation to laboratories outside the lower 48 states. Certification
testing is the central element in the enforcement strategy for this rule.
Frequently, it is essential that EPA observers be present at these tests.
This would obviously be impractical for overseas labs.
Foreign manufacturers may use foreign labs for research and development
(R&D) testing and for QA testing. (Note: if QA testing is conducted
outside the U.S., the results must be kept on file in the U.S). The
requirement that the wood heater be certified in the U.S. should not be
burdensome for a foreign manufacturer who has completed his R&D testing.
The standard requires only that the manufacturer provide one stove out
of each model line to an accredited lab for testing. This imposes no
greater burden on a foreign firm than on a U.S. firm—except for the cost of
shipping, and this cost is no larger proportionally than the cost of
shipping stoves for distribution. The manufacturer has no need to be
present during the testing (and if on-site may serve as an observer only).
There is, therefore, no added personnel cost for foreign manufacturers. In
fact, however, most or all foreign manufacturers do have resident staff
located in the U.S. and these staff do observe certification tests. The
overall effect of the certification requirement is the same for foreign and
U.S. firms. It provides no advantage to U.S. manufacturers and is not in
any way a barrier to trade. It should be further noted that a New Zealand
manufacturer was represented on the negotiation committee. He did not raise
this issue at any time during the development of the rule.
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16.4 Commenter IV-D-26.
Comment: One comtnenter suggested means of reducing variable wood
heater emission performance resulting from construction variability and
recommended that these measures be considered in the laboratory proficiency
test demonstration program. The commenter stated that such measures are
necessary in order to evaluate the inter!aboratory precision accurately.
The commenter listed such measures as gasketing of bypass dampers on
catalyst-equipped wood heaters to prevent leakage and checking of critical
dimensions in the wood heater to ensure that the device is within specific
tolerances. (IV-D-26)
Response: The Agency agrees with the commenter that the measures
mentioned in the comment and other similar checks are important
considerations in evaluating inter!aboratory precision. The Agency is
incorporating these and other such measures into the annual proficiency test
demonstration program for the accredited laboratories.
16,5 Commenters IV-D-21 and 27.
Comment: A laboratory owner suggested a different method for computing
the amount to be deposited into the escrow account for use in the random
compliance audit testing program. He requested that the amount to be
deposited into the escrow account should be 20 percent of a laboratory's
base certification charges rather than 20 percent of a laboratory's final
and total certification charges to the manufacturer. He noted the latter
may include costs for repeated runs, aborted runs, and consulting. He felt
that the escrow deposit should be constant for each stove mode! tested.
(IV-D-25) Another laboratory owner asked EPA to explain the intent of the
words "in trust for the benefit of the Administrator" that are to be used in
designating ownership of the escrow account. (IV-D-27)
Response: EPA has eliminated the escrow account requirement and is
requiring instead the wood heater manufacturer, as a condition of
certification, to enter into a contract with an accredited laboratory.
Under such a contract, the laboratory would be obligated to the manufacturer
for RCA emission testing if one of the manufacturer's stoves were selected
for testing. The manufacturer has ultimate responsibility for bearing the
cost of the test, but the contract with the laboratory provides a means for
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the manufacturer to shift that cost to the laboratory that performed the
certification test by either performing the RCA test or transferring funds
to another laboratory for the purpose of such testing.
Section 17. Quality Assurance Procedures,
17.1 Commenter IV-D-48.
Comment: The proposed quality assurance program was strongly endorsed
by one State regulatory agency. (IV-D-48) Another commenter asked for
clarifications: Must a manufacturer perform QA testing on certified model
lines before the effective date? Before the promulgation date? Does this
answer change if the manufacturer labels and/or advertises stoves as being
certified?
Response: The regulation defines "affected facility" as a wood heater
manufactured on or after July 1, 1988, or sold after July 1, 1990, Thus,
the manufacturer of a certified model line is not required to perform a QA
program before the effective date. However, an ongoing QA program is a
condition of certification. Therefore, if a manufacturer states on a label
that a stove complies with EPA certification requirements, an ongoing QA
program must be in place. Otherwise, this is a violation of the reporting
requirements (Section 60.536 (d)).
17.2 Commenters IV-D-7 and 41.
Comment: A wood heater testing laboratory owner commented that the
requirement in Section 60.533(o)(3)(ii) that the manufacturer's internal
quality assurance (QA) emission testing be conducted using the same test
method used to obtain certification is unfair and unnecessary. He said that
because of this requirement, manufacturers will want to use Method 56 (which
he said is less expensive, less difficult, and less useful for diagnosis and
troubleshooting than Method 5H) for both certification and their
QA programs. Because his laboratory is accredited only for 5H certification
testing, he believes his lab will suffer a "significant loss of business."
He believes this QA test method requirement is contrary to the understanding
that the test methods are equivalent (after applying the correction factor),
(IV-D-7 and 41)
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Response: The cost and convenience of allowing this degree of flexi-
bility outweighs concerns regarding the equivalency of the two methods. EPA
knows of no reason not to allow manufacturers to use either method in their
QA programs. However, in its audit testing programs, EPA intends to use the
test method used in certification. The promulgated regulation has been
changed to reflect this.
17.3 Commenter IV-D-43.
Comment: A State agency objected to the language of 40 CFR 60.533(o)
(3)(i) which indicates the frequency of testing required under the quality
assurance program for stoves where certification test results were "within
30% of standard." This language, the commenter states, suggests that stoves
tested at 130% of the standard would be certified. The commenter suggested
that the language be changed to "...between seventy and one hundred percent
of (the) standard." (IV-D-43)
Response: EPA believes the language as stated in the regulation is
clear. The regulation provides that wood heaters that emit at levels above
the applicable standard (e.g., at 130 percent of the standard) will not be
in compliance (40 CFR 60.532).
17.4
Comment: The Office of Management and Budget commented on the
requirement that manufacturers conduct emission tests as part of their QA
program. OMB argued that the periodic inspection of physical parameters was
adequate to ensure continued compliance for the model line.
Response: EPA is aware of instances where parameter inspections failed
to detect very subtle differences in wood heater construction that resulted
in significantly higher emissions between otherwise identical units.
17.5
Comment: A commenter asked whether manufacturers of Oregon
grandfathered woodstoves [Section 60.530(c)], stoves certified under
alternative certification [Section 60.533(h)], or stoves certified on the
basis that the model is similar in all material respects to already
certified models [Section 60.533(i)] are required to comply with the quality
assurance provisions in Section 60.533(o).
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Response: There are two components to the manufacturer's mandatory
quality assurance program: parameter Inspections to ensure that materials
and dimensions of components critical to emissions remain within tolerance
[Section 60.5333{o)(2}] and emission testing requirements [Section
60.533(o)(3}]. All certified wood heaters are required to meet the
parameter inspection provisions. All certified models, except the
Qregon-grandfathered model, are required to meet the emission testing
provisions. The rationale for excluding the Oregon-grandfathered wood
heaters from the testing provisions is that, since the test method and
emission weighting scheme differs slightly between EPA and the Oregon
regulations, it would not be appropriate to apply EPA test methods to
Oregon-certified wood heaters.
Section 18. Certification Procedures.
18.1 Commenter IV-D-24.
Comment: A State agency noted the similarity between regulating
emissions from woodstoves and from automobiles (numerous, small, moveable
sources). The commenter asked that the enforcement not be delegated to
State and local governments, but rather be retained in a centralized federal
program. Specifically, the State wanted clarification regarding EPA's
intent for state and local responsibility regarding certification,
inspection of retail outlets, laboratory accreditation, emission test
auditing, and the manufacturer's quality assurance program. In particular,
the State pointed out that its regulations exempt from visible emission
limits fuel-burning equipment used to heat buildings containing no more than
two dwellings. The commenter asked how EPA would respond to a legal opinion
that they could not accept NSPS delegation because of the exemption.
(IV-D-24)
Response: The EPA agrees that the implementation of these standards is
similar to the implementation of mobile source emission regulations, and
that a centralized Federal program is the most efficient way to implement
this NSPS. The EPA intends that parameter and labeling inspections will be
the only part of the enforcement program which may be often delegated to
State and local agencies. These consist of inspections of wood heaters at
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retail outlets to determine if the heaters are built to specification and if
labeling requirements are adhered to. An individual State may choose to
either accept or not accept delegation of this program. EPA intends that
certification, laboratory accreditation, and auditing will be carried out
through a centralized program. As to the concern regarding possible
conflicts with the State's visible emission regulations, there is no
conflict because these standards do not address visible emission
requirements.
18.2
Comment: EPA received an inquiry regarding the need for separate
certification of a stove with different exhaust configurations (e.g., top
and rear). Through previous testing, one of the configurations is expected
to result in greater emissions. The following questions were raised: must
a full certification test be run on each configuration? If not, what data
would be needed? If one test run is needed, should this be the dirtiest
test run or the most heavily-weighted test run?
Response: EPA does not now have adequate information to allow it to
determine which configurations result in more emissions, or if a change in
the exhaust configuration will have a similar effect across all burn rates.
Such situations are analogous to "running changes" to an already
certified model line, whereby the Administrator may allow less than a
full-blown certification test if it can be shown (primarily with test data)
to his satisfaction that such changes would not be expected to affect
emissions. However, until such demonstration is made, different wood heater
configurations such as this will be considered different model lines and
will require separate, complete certification tests.
18.3 Commenter IV-D-7,
Comment: A woodstove testing laboratory owner commented that the
requirement that manufacturers provide EPA with 30 days advance notice
conflicts with the practice of scheduling woodstove emission tests. He said
a manufacturer may schedule his product for a certification test, but
subsequently withdraw it after aborting a test series upon determining that
the stove will not pass. In order to maintain cash flow, he continued, it
is important that EPA allow schedule changes which, he said, occur about
twice a week. (IV-D-7)
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Response: The 30-day advance notice requirement is necessary so that
EPA may (1) make plans to observe the test, and (2) be able to forecast the
number of stoves that will be tested and thereby predict whether a "logjam"
exists. On the other hand, EPA recognizes that there is a variety of
legitimate circumstances that arise in wood heater testing and certification
that could cause changes in the schedule. Therefore, the promulgated
regulation has been revised from the proposed version to allow a
manufacturer or a laboratory to change the testing date; however, this
change must be announced by telephone and followup letter at least 14 days
prior to the originally scheduled date. Further, the date cannot be shifted
forward, only backward (i.e., delayed). Finally, if a test date change is
made within the 14-day period, this constitutes a new notification and
therefore starts a new 30-day period.
18.4 Commenter IV-D-22.
Comment: A manufacturer of a combined wood and natural gas stove asked
for clarification as to how the certification procedures would apply to such
a product. (IV-D-22)
Response: As with dual-fired coal and wood heaters, an appliance which
is intended, and advertised, as being capable of burning wood is covered by
the standards and must be tested in a wood-only mode (rather than as a fuel
mixture). This would also apply to gas and wood mixtures.
18.5
Comment: A laboratory spokesman raised questions about the following
situation: A stove can be fitted with a 2-inch combustor, allowing it to
meet the 1988 standard, or a 3-inch combustor, allowing it to meet the 1990
standard. What tests are required? Can the 1990 certification test be done
now even though the stove will not be built until 1990? Are two
contributions to the audit pool necessary?
Response: These stoves would be considered two separate models,
needing separate certification tests. The 1990 certification test may be
done at any time. It is not necessary for the manufacturer to be currently
producing the stove, although it would be necessary to submit the test
report soon after the test was completed. An audit test contribution is no
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longer required. Instead, a contract between the manufacturer and the
laboratory is required for each model tested requiring the laboratory either
to conduct the audit test or pay the cost of audit testing.
18.6 Commenter IV-D-26.
Comment: A State agency commented that it had new test data regarding
the acceptable tolerance limits for variations between the stove tested for
certification and stoves manufactured within the same model lijie
[Section 60.533(k)(2}]. The State said that its test data (which was not
provided or .summarized) indicate that a gap of 0,35 square inches of a
catalyst by-pass will result in a more than doubling of emissions. (IV-D-26)
Response: EPA agrees that the catalyst bypass mechanism may have a
significant effect on emissions. Therefore, by way of clarification, EPA is
adding "catalyst bypass mechanism and catalyst bypass gap tolerances" to the
list of components in Section 60.533(k)(2) which are presumed to affect
emissions. The term "catalyst bypass gap" is not to be construed as the
size of the bypass, but rather is the cross-sectional area of space that
remains after the bypass is closed. It is important that EPA know if the
manufacturer intends for there to be a gap when the bypass is closed, and,
if so, the size of the gap. This should be documented in the engineering
drawings.
EPA does not, though, have sufficient data or information to identify
an appropriate tolerance for catalyst bypass gaps. Nor has there been
demonstrated a readily available, reliable technique for measuring the
catalyst bypass gap. In fact, applicable techniques may differ from stove
to stove, depending on the materials in the mechanism, the size of the gap,
and its accessibility. Therefore, EPA is requiring that the manufacturer,
in his application for 1990 EPA certification, describe a program that will
ensure consistency in the size of any gap in the catalyst bypass mechanism,
should such a gap be part of the design of the stove.
The EPA is aware that catalyst bypass gaps cannot always be measured or
easily accessed after completion of construction of the wood heater. In
such cases, wood heater manufacturers' programs to ensure consistent gaps
should take this into account to avoid problems after construction. In
addition, EPA, in conjunction with the Coalition of Northeast Governors, is
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developing a flow-inducing device that can provide a relative measure of
leakage associated with catalyst bypass gaps. Manufacturers are encouraged
to use such techniques, when developed, to ensure that this critical
parameter remains within specifications.
With regard to the requirement in Method 28, paragraph 6.2, that the
lab measure the size of the gap around the bypass in the closed position on
the stove that has been provided for certification, the Agency recognizes
that there may be some design components that cannot be measured when a
stove is fully assembled as would be the case when it is provided to the
lab. In cases where it is impossible for the lab to verify critical design
parameters without disassembly of the stove, the lab need not make these
measurements and should obtain these measurements from the manufacturer.
18.7
Comment: A manufacturer stated that he typically allows smaller
tolerances on stoves than what EPA allows in Section 60,533(k). These
smaller tolerances appear on all the engineering drawings. For EPA
certification applications, this manufacturer intends to note on the
drawings that the tolerances should be equal to those which are allowed by
EPA. For models which will be "grandfathered" will the manufacturer be held
to the smaller tolerances?
Response: No. EPA tolerances listed in Section 60.533(k) will be
granted to all manufacturers without any need for justification.
18.8 Commenter IV-D-25.
Comment: One commenter raised the issue of how EPA would deal with a
manufacturer who wanted to have an otherwise exempted appliance certified.
The example cited was a pellet stove which would be exempted under the
air-to-fuel ratio cutoff but would benefit from a marketing perspective from
EPA certification. The commenter also said that some State and local
regulatory programs rely on either the Oregon DEQ or the U.S. EPA
certification for determining compliance and that an exempt status is not
sufficient for satisfying these requirements. (IV-D-25)
Response: Technically, an appliance that is not an affected facility
as defined in Section 60.530 of the final rule is not regulated. With
limited resources, EPA does not intend to certify appliances which are
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outside the scope of the regulation's coverage. Pellet burners are
regulated under these standards provided they meet the applicability
requirements of Section 60.530.
18.9 Commenter IV-D-39.
Comment: A commenter suggested that the accredited laboratories should
ensure that wood heaters tested agree with design drawings provided by the
manufacturer prior to sealing the appliance. (IV-D-39)
Response: Although Oregon has such a requirement, Oregon regulations
do not provide for the sealing and storing of the tested unit and,
therefore, Oregon must rely totally on the design drawings. By contrast,
the EPA program can compare the sealed unit with subsequently manufactured
units avoiding the need for solely relying on drawings. Also, manufacturers
are required to submit accurate drawings. If production stoves do not
conform to the drawings or the sealed stove, certification of the model line
may be revoked,
18.10 Commenter IV-D-27.
Comment: Another commenter asked for clarification regarding the
manufacturer's responsibility for reporting proposed changes in any of the
eight emissions-related components listed in Section 60.533(k). (IV-D-27)
Response: The manufacturer must obtain approval from EPA prior to
producing wood heaters with changes in the dimensions (beyond the specified
tolerances) of these components. In seeking approval, the manufacturer must
demonstrate—either on the basis of emissions test data or by other
information--that the proposed change is not likely to cause emissions to
deteriorate. To be in compliance, the manufacturer may not produce wood
heaters that involve changes affecting any of the eight components until he
has received written approval from EPA.
18.11 Commenter IV-D-25.
Comment: One commenter said that the determination of which components
could not be altered without affecting emissions was an engineering decision
that must be made on the basis of technical expertise and experience with
wood heater design and combustion rather than reliance on the provision in
the regulation that limits alterations to specific tolerances for each of
eight specified components. The commenter said that the lack of technical
expertise in EPA's enforcement staff could be avoided by requiring that
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personnel responsible for making engineering judgments on the effect of
emissions from component alterations (and for observing tests and enforcing
the regulation) have an academic degree in engineering or a related science
with a combustion background including experience with wood heaters.
(IV-D-25)
Response: The EPA will ensure that appropriate procedures and trained
staff are available to implement this program.
18.12 Commenter IV-D-25.
Comment: One commenter noted that manufacturers may elect to switch
catalytic combustor brands during the production life of a certified model.
The commenter wanted to know if EPA had provided for this and, if so, how
would combustor equivalency be determined. The commenter asked if
equivalency testing conducted for the Oregon DEQ would be grandfathered or
if a standardized bench test would be developed. (IV-D-25)
Response: As stated in the preamble accompanying the proposed
regulation, prior to July 1, 1990, EPA will allow substitution for catalysts
which have been certified by the Oregon DEQ as equivalent for substitution,
as long as the proposed substitute catalyst had been used in certifying a
currently EPA-certified wood heater. The EPA will develop further guidance
for catalyst manufacturers in demonstrating equivalency for the period after
July 1, 1990.
18.13 Commenters IV-D-25, 27, and 28.
Comment: The EPA received three comments on the requirement that the
laboratory "seal the wood heater on which it performed certification tests,
upon completion of certification testing" [Section 60.535(g)]. A laboratory
owner commented that the requirement should be changed to allow subsequent
inspection or safety testing by the laboratory rather than to require
immediate sealing. The commenter also suggested that tape specific to each
laboratory be used to seal doors, draft controls, and flue collars and that
log books (documenting the sealing action) be maintained for each wood
heater tested for certification purposes. (IV-D-25).
Another laboratory spokesman wanted EPA to clarify that the sealed
stove could be returned to the manufacturer for ultimate storage. (IV-D-27).
A trade association commenter agreed with the need for the provision but, in
order to allow for subsequent safety testing by the same or a different
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laboratory, requested that the regulation allow an independent laboratory to
remove the seals to perform safety testing. The association also suggested
that a log book be maintained documenting when and why the seals were
broken. (IV-D-28) Similarly, EPA has been asked if, Colorado and Oregon
emission testing could be conducted on a stove which had been tested for
EPA.
Response: The EPA requires that the stove be sealed immediately after
certification testing is completed to ensure that the stove will be
available to test if a problem with a model line surfaces later. No
additional testing after the EPA's certification test will be allowed in
order to ensure that the stove can be retested in the same condition as the
original certification test. The safety test could damage the stove, and
the stove could also be damaged inadvertently during other emissions
testing.
The stove should be sealed in a way which will provide evidence of
tampering, i.e., a lab-specific embossed stamp. The stove must be sealed by
the lab, but must be stored at the manufacturer's or importer's facility.
This is a change from the proposed regulation which allowed either the lab
or the manufacturer to store the wood heater. The reason for the change is
to allow EPA more direct comparison of the tested stove with a randomly
selected production stove.
18.14
Comment: EPA was asked if a manufacturer may make repairs to a stove
once it is delivered to the laboratory?
Response: Once the stove is released to the laboratory by the
manufacturer for testing, only minor modifications to the stove may be
allowed upon approval on a case-by-case basis. "Release to the laboratory"
means the date on which certification testing is scheduled to begin
according to the notice sent to EPA.
18.15 Commenter IV-D-26.
Comment: A State agency commented that the altitude restriction on
audit testing among accredited laboratories [Section 60,533(p)(4)(iii)] be
increased from 500 feet to 1,000 feet. The State believes that the
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1,000 foot restriction would cover all of the "low altitude" labs currently
accredited or seeking accreditation and that the 1,000 foot restriction
would be consistent with the test method precision determination in
Section 60.533(p)(4)(ii)(A). (IV-D-26)
Response: The purpose of the plus-or-minus 500-foot requirement is to
eliminate the altitude effect as a variable in wood heater audit testing.
Of the nine accredited laboratories, only one is not within 500 feet of one
or more of the others (this one lab is at an altitude of 6,900 feet and has
applied to EPA for approval of pressurized testing to simulate sea level
conditions). We are aware of no reason why a wider range of altitude is
needed.
18.16 Commenter IV-D-39.
Comment: One woodstove manufacturer suggested that the term
"significant percentage" in reference to the number of parameter inspection
failures which triggers certification revocation in Section 60.533(1)(1)(v)
be more fully defined. (IV-D-39)
Response: Manufacturers should aim to produce all units within
specification. Any unit not produced to specification is in fact not a
certified unit, and if identified during an inspection, may not be sold.
EPA will consider all relevant factors in determining what constitutes a
"significant percentage" of units before revoking certification, and may
consider such factors as the magnitude of the deficiency and its effect on
emissions.
Section 19. Audit Procedures.
19.1 Commenter IV-D-43.
Comment: A State agency wrote stating that it would be unable to
enforce the provisions of the proposed regulation prohibiting stove owners
from operating a stove without a certification label [40 CFR 60.538(a)]
because of the resource limitations of the agency. (IV-D-43)
Response: An individual State may choose either to request or not
request delegation of this part of the regulation. Although EPA agrees that
this provision could be resource-intensive to enforce effectively at the
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consumer level, EPA believes that the provision is necessary to ensure that
only certified heaters are sold and operated. Additionally, monitoring
retail outlets to verify that all stoves sold are properly labeled should
ensure compliance at the consumer level.
19.2 Commenter IV-D-22.
Comment: One commenter expressed concern that the Agency has not
considered emission rate variability in the implementation of the selective
enforcement audit (SEA) and the random compliance audit (RCA). The
commenter listed the three components of this variability as stove-to-stove
differences, inter!aboratory repeatability, and intralaboratory
reproducibility. In addition the commenter asked: (a) How were the
interlaboratory data derived? (b) Are the variability estimates based on
replicate tests of wood heaters and interlaboratory test repetitions? (c)
Is the sample size adequately large to specify an industry-wide variability?
(d) Is the interlaboratory precision allowed by the regulation (+/• 1.0
g/hr) based on a normal distribution? How many standard deviations are
assumed for the stated precision?
The commenter concurred with the Agency's intention to determine
interlaboratory repeatability before implementing enforcement audits, but
urged the Agency to refine the audit program based on statistical
considerations in order to obtain optimal results. (IV-D-22)
Response: The emission limits in the regulation are levels not to be
exceeded when emission tests are conducted using the prescribed test
methods. These emission limits are based upon emission data obtained with
the test methods defined in the regulation. The levels of the standards
reflect the judgment of the negotiating committee and the Agency as to the
achievable level of wood heater performance taking into account several
sources of variability. This includes differences among wood heater designs
and test result imprecision. If these sources of emission rate measurement
variability had not been considered, the emission limits would have been set
at lower levels.
The limited amount of data available to the committee about intralabora-
tory precision (the ability to repeat emission measurements for a single
wood heater) indicated that this precision was within 1.0 g/hr for a four
test run average. The Agency is collecting additional data to determine the
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expected precision before enforcement audits are conducted on an
inter!aboratory basis. Analyses of these data will be conducted in a
statistically sound manner and the results will be published when available.
As described in the preamble to the proposal, the interlaboratory precision
value assumed during the negotiations was 1.0 g/hr. If the results of the
interlaboratory analysis show a value greater than 1.0 g/hr is appropriate,
the revised value will be used in evaluating audit data.
19.3 Commenters 1V-D-20 and 35.
Comment: A manufacturer also objected to the additional costs imposed
by the proposed regulation through the random compliance audit (RCA)
program. The extra 20 percent cost added on for testing will put a burden
on all small manufacturers. (IV-D-20) Another eommenter questioned the
benefit of the RCA, noting that a 20 percent surcharge to the manufacturer
is a high price to pay. This eommenter suggested as an alternative that
in-house quality assurance tests be witnessed by a certified lab technician
during visits made for other reasons. (IV-D-35)
Response: Random emission testing of production line wood heaters is a
crucial part of follow-up enforcement. The negotiation committee created a
program for randomly selecting model lines to test for emissions. This RCA
emission test would apply equally to all model lines certified to the Phase
II emission limits. The total cost of this test, however, would be
significant. In order to reduce the cost impact on the industry, the
committee agreed to perform RCA tests on only one of every five certified
model lines and to provide for sharing the cost of these among all certified
models. This would have been accomplished by requiring that accredited
laboratories establish escrow accounts where all manufacturers of model
lines subject to a possible RCA test would contribute one-fifth of the cost
to the account for each of their certified model lines. As proposed, these
accounts would be set up in trust for the benefit of the Administrator to
pay for the cost of the RCA tests.
The proposed method of financing the cost of conducting the RCA tests
has been modified to clarify that there was no intent to supplement EPA
appropriations.
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The rule has been revised by eliminating the requirement to establish
an escrow account for the benefit of the Administrator. Instead, wood
heater manufacturers, as a condition of certification, would enter into an
RCA testing contract with the laboratory that conducts the certification
test. Under such a contract, the laboratory would be obligated to the
manufacturer for RCA emission testing if one of the manufacturer's stoves is
later selected for testing. The manufacturer has legal responsibility for
bearing the cost of the test. However, the contract with the laboratory
provides a means for the manufacturer to shift that responsibility to the
laboratory which performs the certification test by requiring them either to
perform the RCA test or transfer funds to the laboratory selected by EPA for
such testing.
19.4 Commenter IV-D-20.
Comment: A manufacturer stated that the RCA should be performed by
comparing as-built stoves with the blueprints for that stove submitted at
the time of certification. The stove should be within specified tolerances
to pass. If there are complaints about the emissions from a particular
stove line, EPA should demand that the unit be retested at the manufactur-
er's expense. (IV-D-20)
Response: The EPA already intends to conduct the kind of inspection
described by the commenter. This is the parameter inspection program. It
may involve use of engineering drawings as well as examination of the sealed
stove. However, it is not a substitute for the RCA. The purpose of the RCA
is to evaluate the emissions directly (rather than construction quality) of
production-line stoves. The RCA is a quality assurance step that was chosen
to respond to concerns identified in the Oregon wood heater certification
program and that have subsequently been observed by EPA in replicate tests
on production stoves. The committee agreed that relying solely on one test
with the manufacturer present (but possibly not EPA) would not provide
sufficient assurance of quality.
19.5 Commenter IV-D-20.
Comment: This same commenter stated that if the RCA requirement cannot
be eliminated from the standards, it ought to be changed so that the
selection of stoves to be tested does not disadvantage the manufacturer who
produces a relatively small number of stoves but a large number of different
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models. The commenter recommended that the proposed standards be changed to
allow a manufacturer whose models pass inspection be exempted from further
testing for a period of time for all models, unless there are complaints
against the manufacturer or model. (IV-D-20)
Response: The EPA believes that each model should stand alone
regardless of how many models are made by a single manufacturer or how often
the manufacturer may have been selected for audit testing. Each model is
different and has different emission characteristics. The anticipated costs
of compliance should be considered by the manufacturer in the decision to
produce and market each stove model.
19.6 Commenter IV-D-8.
Comment: A manufacturer of ceramic wood heaters said that EPA's
selection of five randomly-chosen wood heaters for audit testing [Section
60.533(p)(2)] may be practical for mass-produced metal woodstoves, but would
cause hardship and inconvenience for ceramic products which are made to
order using customer-designated color combinations. He said the impoundment
of wood heaters for audit testing would cause serious delays for customers
awaiting their order. He also wanted to know if EPA would bear the
additional cost of constructing a replacement unit. (IV-D-8)
Response: Audit testing described in Section 60.533(p)(2) is EPA's
only means to ensure that production line wood heaters continue to meet the
standards. Although five heaters are selected for audit, only one heater is
tested. The other heaters are tested only if the first heater fails. The
commenter may avoid extreme adverse economic effects by ensuring that each
of his heaters can meet EPA's standards. The EPA cannot waive audits on
custom-built stoves without jeopardizing its ability to ensure the emission
reduction anticipated by the standards. It is the manufacturer's
responsibility to supply a stove for audit testing, and as such, any
associated cost is a part of his cost of doing business.
Section 20. Reporting and Recordkeeping.
20.1 Commenters IV-D-29 and IV-D-42.
Comment: Two commenters {IV-D-29 and IV-D-42) stated that the names
and addresses of wood heater purchasers, required by Section 60.537(d) to be
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maintained by all commercial owners, should be made available to State and
local agencies for developing educational and regulatory programs to reduce
woodstove emissions. However, the Office of Management and Budget (OMB),
which is charged by law to review proposed regulations for excessive
paperwork requirements, recommended that this provision be eliminated.
Response: The EPA agrees with OMB that this provision is unnecessary
and that the potential burden imposed by this requirement exceeds any
benefits that might accrue. The provision was originally conceived as a
means by which EPA could assist manufacturers in alerting stove purchasers
of noncomplying wood heaters or defective control equipment. Moreover, many
commercial owners already maintain these types of records for marketing
purposes anyway, and EPA has authority to request these records. Therefore,
if there is a need to notify owners of wood heaters, EPA can do so without
any additional recordkeeping provision.
Section 21. Labeling.
21.1 Commenter IV-D-1.
Comment: One commenter believed that heat output value reported on the
temporary label will be understated because the testing protocol results in
artificially low drafts. He felt that this would result in consumers
oversizing their stoves and causing more pollution than necessary, since
they would have to operate the stove more in the low heat output range where
highest emissions are generated. The natural draft in real world conditions
(i.e., cold outside chimney temperatures) may be two to three times as high
as in the test laboratory because a temperature differential between the
firebox and the chimney exits. He felt that Appendix I of the regulation
should discuss what affects draft and he said this factor is "crucial."
(IV-D-1)
Response: The effect of draft variability (from the variation in
chimney temperature differentials) on a consumer's stove sizing decision is
merely one of many variables affecting stove sizing and may be offset by the
other factors. Woodstove retailers may be able to help consumers in
determining the heat outputs they require. Appendix I does contain a
section on "Achieving Proper Draft."
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Response: The negotiation committee spent much time and deliberation
21,2 Commenter IV-D-26,
Comment: A State agency commented that paper hang tag temporary labels
had become their greatest enforcement problem. Retailers in that State
report that the labels are frequently damaged or removed by customers. The
State recommended that self-adhesive removable labels be required. (IV-D-26)
Response: Appendix I of the regulation has been revised to permit, but
not require, self-adhesive removable labels or laminated tags which could be
used for models on dealer show room floors. Actual units delivered to the
client could still have paper tags for sake of economy. The actual decision
of how to ensure that all wood heaters are properly labeled would be up to
manufacturer, distributor, and retailer.
21.3 Commenter IV-D-32.
Comment: A local air pollution control district recommended that the
labeling and owner's manual requirements be revised to show consumers the
significant personal benefits of proper use and maintenance of catalytic
woodstoves. The benefits the commenter recommended be included on the label
and/or in the owner's manual include: (1) the increased safety of catalytic
stoves resulting from the reduction in creosote build-up; (2) the reduced
fuel costs associated with the more efficient combustion achievable with
catalytic stoves; and (3) the improvements in indoor and outdoor air quality
achievable. The commenter urged the adoption of these recommendations
because the currently proposed labeling requirement stating that operation
without a catalyst is "against the law" is inadequate to motivate woodstove
owners to replace or maintain catalysts as needed. (IV-D-32)
on contents of labels and owner's manuals. The consensus was that the
permanent label should provide only essential identifying and enforcement
data, and that the temporary label and owner's manual should address
operation and maintenance including benefits. Individuals knowledgeable
with consumer response to labeling indicated that purchasers will not read
detailed hang tags and therefore the labels should contain only a brief
amount of essential information related to wood heater selection.
Nevertheless, the temporary label does tell the consumer that "this wood
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heater will achieve low smoke output and high efficiency only if properly
operated and maintained." EPA encourages but does not require manufacturers
to stress the benefits of catalyst replacement and care in their owner's
manual.
21.4 Commenter IV-D-1.
Comment: One commenter felt that either on the label or in a separate
format, EPA should disclose other relevant data obtained from certification
testing such as burn times, CO measurements, excess air, and stack
temperatures. He also believes that graphs that show emissions and
efficiency as a function of burn rate (as do those required by Oregon DEQ)
would also be helpful. (IV-D-1)
Response: EPA believes that these detailed data are beyond what is
needed and useful to most consumers. Further, these detailed data can be
misleading to the general public who are not familiar with stove testing,
EPA will develop material to be updated periodically and to be made
available to the public upon request. This material will provide
comparative test data, including some of that requested by the commenter,
and other data (such as firebox sizes).
21.5 Commenter IV-D-28.
Comment: A manufacturer's trade association recommended modifying
slightly the design of the temporary labels by reducing the number of type
styles to a single easily read font. As provided for in the negotiated
agreement, the association submitted the revised labels. (IV-D-28)
Response: The EPA agrees with the labels submitted by the trade
association and has revised Appendix I to include the revised labels.
21.6
Comment: The EPA was asked what values should be used for efficiency
and heat output ranges on the temporary label for Oregon "grandfathered"
stoves? (i.e., should these values be the values approved by Oregon, or
should the default value for efficiency be used?)
Response: The EPA has not yet proposed a method to measure efficiency.
The standards require manufacturers to use a default efficiency if they
choose not to test efficiency or if they choose to test before a method is
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available. The default efficiency was included so that consumers can make
meaningful distinctions between catalytic and noncatalytic stoves.
Efficiency testing by a method other than an EPA method would be confusing
to consumers, and inclusion of Oregon efficiencies would not provide a
useful basis for comparison. Therefore, manufacturers of Oregon
"grandfathered" stoves are required to use the default value for efficiency
and heat output ranges.
21.7
Comment: The Office of Management and Budget initially expressed
reservations about the requirement that a wood heater's efficiency be
reported on the temporary label because efficiency ratings are imprecise and
thereby potentially misleading, an additional cost to manufacturers, and not
within EPA's purview.
Response: Although EPA shared some of these concerns, especially
regarding precision, this issue was thoroughly discussed during the
regulatory negotiating sessions. The resulting compromise, which provides
for default values to those manufacturers who wish to avoid the extra cost
of efficiency testing and which provides consumers with an approximate
relative indicator of efficiency, satisfies these concerns as well as those
of the environmental and consumer representatives (and many manufacturers)
who want EPA to standardize efficiency values. Standardized reporting of
stove efficiency, at a minimum, ensures that efficiency data are not
intentionally misrepresented in a manner that would be detrimental to both
consumers and the environment.
Section 22. Consumer Education.
22.1 Commenters IV-D-29 and 46.
Comment: A regional association of States noted that State and local
officials could play an important role in implementing and enforcing the
regulation. The organization cited several options to improve in-use
performance, and encouraged EPA to provide funding for these activities.
Some of the improvement options mentioned were: visible emission limits,
anti-tampering devices, an inspection and maintenance program, a licensing
program, a proficiency exam, annual maintenance reminders for stove owners,
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education, and a field applications coordinator to help stove owners. Also,
a State air quality agency and an organization of State agencies commented
that correct in-use operation of catalytic woodstoves is essential to
achieving the emission reductions sought in the standards. They urged EPA
to budget funds which would be used to encourage State and local officials
to develop, implement, and enforce innovative methods for educating
woodstove owners on proper stove operation, or for overseeing or regulating
in-home stove use. The State agency said the program could be funded
through a tax levied against each certified stove. (IV-D-29 and 46)
Response: The EPA will develop a consumer education program that will
address many of the concerns expressed by the commenter. However, EPA does
not intend to levy a tax on each certified wood heater sold. The Agency
agrees that installation, operation, cleaning, and maintenance are factors
which can affect emissions. To the extent that local agencies could promote
these actions, this would enhance the effect of the regulation. State fees
could be a means to support such activities. This could be a means by which
State and local authorities could raise revenue to support the programs the
commenter is suggesting.
22.2 Commenter IV-D-18.
Comment: One commenter stated that the regulation should not require
high levels of sophisticated knowledge to operate and maintain a wood
burning stove. A woodstove should be operable by members of the general
population who, in many areas, may only have a rudimentary education.
(IV-D-18)
Response: By forcing all models to undergo a standardized testing
protocol (to demonstrate compliance), the standards indirectly ensure
against the possibility that esoteric operating practices will be required
in order to meet the standards. Wood heaters currently offered for sale are
relatively easy to operate. Also, manufacturers are motivated by market
competition to keep wood heater designs "user friendly."
22.3 Commenter IV-D-18.
Comment: One commenter urged EPA to train county agricultural
extension agents and local fire departments on the cause of fires from
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woodstoves, particularly the production of creosote from the deficiency of
air. These personnel could be supported by traveling EPA personnel who
could show homeowners how to operate their stoves properly. (IV-D-18)
A commenter also urged EPA to provide support and funding for the
development of educational materials instructing stove owners in the proper
operation and maintenance of catalytic woodstoves. The materials might
include videotapes or written materials in addition to the owner's manual.
(IV-D-29)
Response: EPA is planning to develop public education activities.
There are currently available several good, free publications on woodstove
selection, installation, and operation which may be identified in EPA
brochures.
22.4 Commenter IV-D-43.
Comment: A State agency recommended that instructions be put in the
owner's manual for following EPA's method (40 CFR 60 Appendix A, Method 9)
for distinguishing between steam and smoke emissions. This would prevent
confusion on the part of woodstove owners attempting to monitor the
performance of their catalytic woodstoves. The agency also said that smoke
reading could be a desirable field enforcement tool for monitoring new
woodstoves installed in heavily affected areas, (IV-D-43)
Response: Appendix I already encourages the inclusion of wording in
the owners manual to assist stove owners in distinguishing between smoke and
steam. Opacity readings can be a useful technique for detecting high
emitting stoves although EPA does not have data relating BDT to opacity.
22.5 Commenter IV-D-18.
Comment: One commenter urged that the standards be revised to include
a provision requiring owners or operators of woodstoves to construct a wood
drying shed to protect fire wood from rain and snow and allow air movement
through the wood. This shed should be fixed to hold a year's worth of
cordage. In the commenter's opinion, the addition of a woodshed and the
proper drying and storage of wood as a requirement would help reduce air
emissions. (IV-D-18)
Response: The EPA believes this is not appropriate in a national
standard. While a shed for wood drying may be beneficial, there are other
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less costly means of protecting wood from rain or snow. In addition, some
owners—particularly in densely populated areas—do not have space for
drying sheds or for more than a small supply of wood.
Section 23. Cost and Economic Impacts.
23.1 Commenter IV-D-18.
Comment: One commenter felt that catalyst replacement costs of $50 to
$75 were prohibitive on a 2-year replacement basis. This commenter stated
that any regulation promulgated to solve the problem of pollution from
woodstoves should not undercut the use of wood as a means of home heating
that is extensively used by low-income people. The regulation should not
make wood burning increasingly costly, thereby discouraging its use by
depressed, high unemployment communities. (IV-D-18)
Response: By promoting more efficient combustion, the standards reduce
rather than increase the total cost of wood burning. Catalysts are expected
to last at least a total of 10,000 hours of operation. Cost savings over
time would more than offset the cost of catalyst replacement. Also, the
second-hand stove market will continue to provide an outlet for inexpensive
wood heaters for those unable to bear the initial costs of certified stoves.
23.2 Commenter IV-D-24.
Comment: A commenter said the impact of the standards falls
particularly hard on rural homeowners, and that the imposition of this rule
is probably not needed in rural areas because of the relatively clean air in
these areas. The commenter used the following hypothetical cost figures to
illustrate his point: an increase in new stove costs from $400 (without a
catalyst) to $600 with a catalyst; and $150 catalyst replacement costs. His
conclusion was that the standards would add significantly to the cost of
owning and operating a new woodstove. The commenter concluded that cost
increase may penalize the rural population which is heavily dependent on
woodstoves for home heating. (IV-D-24)
Response: The EPA estimates that the wood heater price increases
resulting from the addition of catalytic and noncatalytic controls will be
about $200 and $120 respectively. However, because of the increased
efficiencies and the reduced chimney cleaning costs resulting from the use
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of certified wood heaters, the actual cost of heating will decline. Net
savings is greatest for those homes that burn the most wood. The EPA
estimates that in the fifth year after the emission limits take effect
(1993), the national reduction in wood heating costs will be about $29
million annually.
23.3 Commenter IV-D-24.
Comment: The State of Tennessee commented that there are six major
manufacturers in the State (employing from 140 to 350 persons per plant)
that could be affected by the rule. The State collected comments from
manufacturers who noted concern that the additional capital outlay required
to comply with the standards could result in plant closings or layoffs.
(IV-D-24)
Response: Firms will incur capital compliance costs over several years
as redesign and certification proceeds and as the NSPS moves from the
initial 1988 emission limits to the more stringent 1990 limits. The capital
outlay required to comply with the NSPS depends on many factors. Among
these are the number of models that require engineering and design
modifications as well as safety and emission tests, retooling costs (a
function of the size of the production lines), licensing costs (for
manufacturers electing to purchase approved designs from other firms),
market development costs, and type(s) of heater to be produced. For some
firms capital compliance costs will be negligible because the firms already
are producing low-emitting models, or would be redesigning their model lines
as a matter of course and not because of the NSPS. For other firms the
capital outlay may be substantial which, the commenter says, is the case
with some manufacturers in Tennessee.
Capital outlay, markups, and production cost increases all will affect
market prices of heaters. All factors considered, EPA estimates that on
average the NSPS could result in an increase in retail prices of new heaters
by $120 to $200. These new heaters, of course, will be more efficient and
less polluting than the models they replace. In most cases the $120 to $200
will be quickly recouped by owners because of reduced fuel wood and chimney
cleaning expenses. EPA projects that the price increase could cause a five
to seven percent nationwide decline in wood heater production and sales.
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Such a decline in production might be absorbed by the highest-cost
manufacturers, or it might be absorbed more-or-less equally by all
manufacturers. In the first case, if smaller-volume manufacturers are the
highest-cost manufacturers—they have fewer units over which to spread
capital expenditures—as many as 60 percent of firms that specialize in
conventional heaters and produce fewer than 5,000 units per year may decide
to get out of the wood heater business. However, this scenario ignores
transportation costs, product differentiation, and joint production of other
items with wood heaters. In the second case, where the production decline
is absorbed by all manufacturers, very few would leave the wood heater
market.
The EPA does not know the specific financial conditions and production
costs faced by the firms referred to by the commenter. However, employment
in the range of 140 to 350 persons per firm implies production volumes well
in excess of 10,000 units per firm per year. (About 1000 heaters are
produced for every employee in the industry, on average, but this production
rate varies greatly among firms.) Thus, these Tennessee manufacturers
probably are not firms that have high production costs because of low
production volume. In fact, production volumes appear to be high enough to
make it fairly easy for them to write off capital compliance costs.
The EPA has several reports of estimated capital compliance costs. One
of the highest figures is from a cast iron manufacturer, not in Tennessee,
who had developed a completely new top-of-the-line catalytic heater on a
14-month schedule. Although the total development cost includes designing
and testing the model, revamping the production line and retraining workers,
and establishing a market for the model, only about $80,000 is directly
associated with implementing catalytic technology in a new combustion
system. A firm that can borrow at 10 percent interest and that produces
10,000 of the redesigned heaters per year can write off $80,000 in five
years by adding about $2.10 to the wholesale price of each heater, or in
three years by adding about $3.20 to the wholesale price of each heater.
Even if the firm produces half as many redesigned heaters, the wholesale
price increases are minimal. This manufacturer's costs are atypical; most
are expected to incur lower costs. For example, manufacturers that wish to
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forgo research and development expenditures may purchase detailed blueprints
and technical instruction from firms that have obtained certification for
heaters produced from those blueprints. In one case reported to EPA, the
purchase price for a catalytic design certified by Oregon begins at $500.
On-site technical assistance, training, and other services may add $2,000 or
more, but when it is all added up the capital outlay will be substantially
less than in the $80,000 example above.
The one-year compliance grace period will give the smallest
manufacturers extra time to make the capital expenditures necessary to meet
the NSPS. If there are Tennessee firms that produce fewer than 2,000
heaters per year, this grace period, together with the ability to purchase
an approved design for a modest price, will make it easier and less costly
for them to comply.
The EPA concludes that although the Tennessee plants may have to lay
off a few workers or transfer them to other production lines, the
displacements are likely to be minimal.
23.4 Commenter IV-D-38.
Comment: Another commenter noted the adverse impacts of the standards
on small manufacturers. This commenter felt that the type of stove made by
his small company in Maine would have trouble complying with the standards
due to climatic conditions (his customers need very high heat output
stoves). The commenter recommended that existing models of very small
manufacturers (limit of 200 units per year) be grandfathered and that the
standard be applied to existing small manufacturers only with respect to new
models. (IV-D-38)
Response: The EPA realizes that many wood heater model lines may have
to be modified to meet the standards. The regulation gives the small (i.e.,
fewer than 2,000 units per year production) manufacturers an additional year
to comply and allows firms who manufacture a stove similar to an
already-certified stove to avoid certification testing costs. Also,
manufacturers of model lines of less than 2500 units per year and with
certified emission levels less than 70 percent of the applicable emission
limit, are not required to conduct QA emission testing unless directed by
EPA. The committee considers these
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provisions adequate to enable these manufacturers to compete. Permanent
exemptions from the standard on the basis of manufacturer size could be used
as a means of circumvention and would be unfair to those firms that are
making the effort to comply.
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing;
1.
4,
7,
9.
12
16
REPORT NO. 2.
EPA-450/03-87-Q25
TITLE AND SUBTITLE
New Residential Wood Heaters - Background
Information for Promulgated Standards
AUTHOR(S)
PERFORMING ORGANIZATION NAME AND ADDRESS
Standards Development Branch
Environmental Protection Agency
Research Triangle Park, North Carolina 27711
. SPONSORING AGENCY NAME AND ADDRESS
DAA for Air Quality Planning and Standards
Office of Air and Radiation
U.S. Environmental Protection Agency
Research Trianqle Park, North Carolina 27711
3. RECIPIENT'S ACCESSION NO,
5. REPORT DATE
November 1987
6, PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATION REPORT NC
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
13. TYPE OF REPORT AND PERIOD COVEHEI
14. SPONSORING AGENCY CODE
EPA/200/04
, SUPPLEMENTARY NOTES
16. ABSTRACT
Manufacturers of residential wood heaters would be required to meet certain
standards limiting emissions of participate matter. EPA would certify wood
heaters models by conducting certification tests at accredited laboratories
on representative wood heaters. This report contains background technical
information used in establishing these standards.
17. ' KEY WORDS AND DOCUMENT ANALYSIS
1, DESCRIPTORS
Air pollution
Pollution control
Standards of performance
Particulate matter
Intergovernmental relations
Reporting and recordkeeping
18. DISTRIBUTION STATEMENT
Unl imi ted
b.IQENTIFIERS/OPEN iNOSD TERMS
Air pollution control
19. SECURITY CLASS (This Report!
Unclassified
20. SECURITY CLASS (Tltii page)
Unclassified
c. COSATI Field/Croup
21. NO. OF PAGES
125
22. PRICE
IPA Form 2220-1 (R«v. 4-77) PREVIOUS EDITION is OBSOLETE
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