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Environmental Technology
Verification Program
Advanced Monitoring
Systems Center
Test/QA Plan for
Verification of Portable
Gaseous Emission Analyzers
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TEST/QA PLAN
FOR
VERIFICATION OF
PORTABLE GASEOUS EMISSION ANALYZERS
January 3, 2002
U.S. EPA Environmental Technology Verification (ETV) Program
Advanced Monitoring Systems (AMS) Center
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DISTRIBUTION LIST
Ms. Elizabeth A. Betz
U.S. Environmental Protection Agency
National Exposure Research Laboratory
MD-44
Research Triangle Park, NC 27711
Mr. Robert Fuerst
U.S. Environmental Protection Agency
National Exposure Research Laboratory
MD-46
Research Triangle Park, NC 27711
Dr. Thomas J. Kelly
Verification Testing Leader
ETV Advanced Monitoring
Systems Center
Battelle
505 King Avenue
Columbus, OH 43201-2693
Ms. Elizabeth Hunike
Quality Assurance Specialist
U.S. Environmental Protection Agency
National Exposure Research Laboratory
ERC Annex, MD-46
Research Triangle Park, NC 27711
Mr. William Welch
Principal Development Engineer
Center for Environmental Research
and Technology
1200 Columbia Avenue
Riverside, CA 92507
Ms. Karen Riggs
AMS Center Manager
Battelle
505 King Avenue
Columbus, OH 43201-2693
Mr. Charles Lawrie
AMS Center Quality Manager
Battelle
505 King Avenue
Columbus, OH 43201-2693
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CONTENTS
Page
1.0 INTRODUCTION 1
1.1 Test Description 1
1.2 Test Objective 1
1.3 Organization and Responsibilities 1
1.3.1 Battelle 2
1.3.2 Test Facility 5
1.3.3 Vendors 8
1.3.4 EPA 8
2.0 APPLICABILITY 9
2.1 Subject 9
2.2 Scope 10
3.0 DEFINITIONS 12
4.0 SITE DESCRIPTION 16
4.1 General Site Description 16
4.2 Site Operation 16
4.3 Emission Sources 16
4.3.1 Commercial Range Burner Cooktop 17
4.3.2 Small Diesel-Fueled Engine 17
4.4 Operation of Sources 18
4.4.1 Commercial Range Burner Cooktop 18
4.4.2 Small Diesel-Fueled Engine 19
5.0 EXPERIMENTAL DESIGN 19
5.1 General Description of Verification Test 19
5.2 Reference Methods 20
5.3 Laboratory Tests 21
5.4 Combustion Source Tests 21
5.5 Additional Performance Factors 21
5.5.1 Inter-Unit Repeatability 22
5.5.2 Data Completeness 23
5.5.3 Cost 23
5.6 Test Schedule 24
6.0 MATERIALS AND EQUIPMENT 24
6.1 Gases 24
6.1.1 EPA Protocol Gases 24
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CONTENTS (Continued)
6.1.2 Interference Gases 26
6.1.3 High Purity Nitrogen/Air 26
6.2 Reference Instruments 26
6.3 Dilution System 27
6.4 Temperature Sensors 27
6.5 Gas Flow Meters 27
7.0 TEST PROCEDURES 28
7.1 Linearity 29
7.2 Response Time 30
7.3 Detection Limit 31
7.4 Interferences 31
7.5 Ambient Temperature 33
7.6 Interrupted Sampling 34
7.7 Pressure Sensitivity 34
7.8 Accuracy 36
7.9 Zero/Span Drift 37
7.10 Measurement Stability 38
8.0 QUALITY ASSURANCE/QUALITY CONTROL 38
8.1 Instrument Calibration and Frequency 38
8.1.1 Reference Method Monitors 38
8.1.2 Gas Dilution System 39
8.1.3 Temperature Sensor/Thermometers 39
8.1.4 Gas Flow Meters 39
8.2 Assessments and Audits 40
8.2.1 Pre-Test Laboratory Assessment 40
8.2.2 Technical Systems Audits 40
8.2.3 Performance Evaluation Audit 41
8.2.4 Data Quality Audits 42
8.3 Assessment Reports 42
8.4 Corrective Actions 42
9.0 DATA ANALYSIS AND REPORTING 43
9.1 Data Acquisition 43
9.2 Statistical Calculations 46
9.2.1 Linearity 46
9.2.2 Response Time 47
9.2.3 Detection Limit 48
9.2.4 Interferences 49
9.2.5 Ambient Temperature Effect 49
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CONTENTS (Continued)
9.2.6 Interrupted Sampling 49
9.2.7 Pressure Sensitivity 50
9.2.8 Accuracy 50
9.2.9 Zero/Span Drift 51
9.2.10 Measurement Stability 51
9.2.11 Inter-Unit Repeatability 51
9.2.12 Data Completeness 52
9.3 Data Review 52
9.4 Reporting 53
10.0 HEALTH AND SAFETY 54
10.1 Access 54
10.2 Potential Hazards 54
10.3 Training 55
10.4 Safe Work Practices 55
11.0 REFERENCES 56
FIGURES
Figure 1 - Organization Chart for the Verification Testing 3
TABLES
Table 1. Summary of Laboratory Tests 22
Table 2. Summary of Combustion Source Tests 23
Table 3. Schedule of Verification Testing Activities 25
Table 4. Summary of Interference Tests to be Performed 32
Table 5. Summary of Data to be Collected for Accuracy Determination in the
Combustion Source Tests 37
Table 6. Summary of Performance Audit Procedures 41
Table 7. Summary of Data Recording Process for the Verification Test 45
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1.0 INTRODUCTION
1.1 Test Description
This test/QA plan provides detailed procedures for a verification test of portable
analyzers used to measure gaseous concentrations of nitrogen oxides (NO and N02, collectively
denoted as NO,), carbon monoxide (CO), sulfur dioxide (S02), and oxygen (02) from small
combustion sources. The verification test will be conducted under the auspices of the U.S.
Environmental Protection Agency's (EPA) Environmental Technology Verification (ETV)
program. The purpose of ETV is to provide objective and quality-assured performance data on
environmental technologies, so that users, developers, regulators, and consultants have an
independent and credible assessment of what they are buying and permitting.
This verification test will be performed by Battelle, of Columbus, Ohio, which is EPA's
verification partner for the ETV Advanced Monitoring Systems (AMS) Center. The scope of the
AMS Center covers verification of monitoring methods for contaminants and natural species in
air, water, and soil. In performing the verification test, Battelle will follow procedures specified
in this test/QA plan, and will comply with quality requirements in the "Quality Management
Plan for the ETV Advanced Monitoring Systems Center" (QMP),'"
1.2 Test Objective
The objective of the verification test is to quantify the performance of commercial
portable emission analyzers, by comparisons to standards or to reference methods, under
controlled laboratory conditions as well as with realistic emission sources.
1.3 Organization and Responsibilities
The verification test will be performed by Battelle in cooperation with EPA and the
vendors who will be having their analyzers verified. The test procedures may be performed by
Battelle, or by a test facility working under subcontract from Battelle. An organization chart for
the verification is shown in Figure 1. In an initial verification under this test/QA plan, the test
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facility will be the Bourns College of Engineering - Center for Environmental Research and
Technology (CE-CERT) at the University of California, Riverside. As the test facility, CE-
CERT's involvement is subject to Battelle's and EPA's oversight of all planning, testing, and
data quality activities. Other qualified test facilities may be used, subject to the same Battelle
subcontracting requirement and quality oversight. Throughout this test/QA plan, reference to
CE-CERT's role and responsibilities should be taken to indicate as well those of Battelle or any
suitably qualified subcontracted test facility.
Specific responsibilities in each of several areas for verification within ETV are detailed
in the following paragraphs.
1.3.1 Battelle
Dr. Thomas J. Kellv is the AMS Center's Verification Testing Leader. In this role, Dr.
Kelly will have overall responsibility for ensuring that the technical, schedule, and cost goals
established for the verification test are met. More specifically, Dr. Kelly will:
Establish a subcontract with the test facility, or organize testing using Battelle staff and
facilities.
Coordinate with the test facility to conduct the verification test
Coordinate the review of the draft test/QA plan
• Have overall responsibility for ensuring that the test/QA plan is revised, and followed during
the verification tests
• Oversee initial verification testing, including visiting the subcontracted test facility at the
start of testing
• Prepare the draft ETV verification reports and statements, based on test data reports from the
testing laboratory
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Figure 1. Organization Chart for the Verification Test
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• Revise the ETV verification reports and statements in response to vendors' and reviewers'
comments
• Coordinate distribution of the final test/QA plan, verification reports, and statements
• Coordinate with the test facility in responding to any issues raised in assessment reports and
audits, including instituting corrective action as necessary
Serve as Battelle's primary point of contact for vendor and test facility representatives
• Establish a budget for the verification test and monitor the effort to ensure that budget is not
exceeded
• Ensure that confidentiality of vendor information is maintained.
Ms. Karen Riggs is Battelle's AMS Center manager. As such, Ms. Riggs will:
• Review the draft test/QA plan
• Review the draft ETV verification reports and statements
• Ensure that necessary Battelle resources, including staff and facilities as necessary, are
committed to the verification test
• Ensure that vendor confidentiality is maintained
Support Dr. Kelly in responding to any issues raised in assessment reports and audits
• Maintain communication with EPA's Center Manager.
Mr. Charles Lawrie is Battelle's Quality Manager for the AMS Center. As such, Mr.
Lawrie or his designee will:
• Review the draft test/QA plan
• Maintain communication with EPA's Quality Manager for the AMS Center
Serve as the primary point of contact with the test facility's QA/QC Manager
• Review information on the test facility's training records, calibration procedures, standard
operating procedures (SOP's), etc., before any testing
• Conduct a technical systems audit during the verification test
• Review results of performance evaluation audit(s) specified in this test/QA plan
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• Audit 10% of the verification data
• Prepare and distribute an assessment report for each audit
• Verify implementation of any necessary corrective action
• Issue a stop work order if internal audits indicate that data quality is being compromised;
notify Battelle's AMS Center Manager if such an order is issued
• Provide a summary of the QA/QC activities and results for the verification reports
• Review the draft ETV verification reports and statements
• Ensure that all quality procedures specified in this test/QA plan and in the QMP(1) are
followed.
1.3.2 Test Facility
The key responsibilities of the subcontracted test facility are indicated in this section,
with CE-CERT staff exemplifying the roles required of any such test facility.
The CE-CERT Program Manager (William Welch) will have overall responsibility for
the performance of verification test procedures at CE-CERT. More specifically, Mr. Welch will:
Assist in establishing a subcontract to perform the work, and adhere to the terms and
conditions of that subcontract
Assemble a team of qualified technical staff to conduct the verification test
Prepare the draft test/QA plan
Coordinate performance of the verification test in accordance with the test/QA plan
Ensure that all quality procedures specified in this test/QA plan and in the QMP are followed
Respond to any issues raised in assessment reports and audits, including instituting corrective
action as necessary
Serve as CE-CERT's primary point of contact for vendor, EPA, and Battelle representatives
Ensure that confidentiality of vendor information is maintained
Ensure that necessary CE-CERT resources, including staff and facilities, are committed to
the verification test
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Prepare a test data report for each portable emission analyzer tested, summarizing the
procedures and results of the verification test, and including copies and supporting
information for all raw test data. Submit this test data report to Battelle within the schedule
specified in the subcontract.
Support the Battelle Verification Testing Leader in responding to any issues raised in
assessment reports and audits
Maintain communication with Battelle's Verification Testing Leader and Quality Manager.
CE-CERT's Source Operations and Testing Leader (C. Anthony Taliaferro) will be
responsible for conducting the verification tests. More specifically, he will:
Assemble trained technical staff to operate each combustion source and the reference
methods for the verification test
Ensure that each combustion source is committed to the verification test for the times and
dates specified in the verification test schedule
Ensure that each combustion source is fully functional prior to the times and dates of the
verification test
Oversee technical staff in combustion source operation and reference method performance
during the verification test
Ensure that operating conditions and procedures for each combustion source are recorded
during the verification test
Review and approve all data and records related to emission source operation
Adhere to the quality requirements in this test/QA plan and in the QMP
Provide input on combustion source operating conditions and procedures for the test data
report on each analyzer tested
Assist vendors in the setup of the portable analyzers for verification tests
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Provide daily on-site support (e.g., access to telephone or office facilities; escort through CE-
CERT laboratories; basic laboratory supplies) to vendor, EPA, and Battelle representatives
as needed
Document any repairs and maintenance conducted on the analyzers, including description of
repair and maintenance performed; vendor time required to perform repair or maintenance;
and amount of analyzer downtime
Support the CE-CERT Program Manager and Battelle in responding to any issues raised in
assessment reports and audits related to combustion source operation or analyzer
performance.
The CE-CERT Statistics and Data Analysis Leader (Theodore Younglove) will provide
statistics and data analysis support, including:
Converting analyzer and reference data from electronic spreadsheet format into appropriate
file format for statistical evaluation
Performing statistical calculations specified in this test/QA plan on the analyzer data
Providing results of statistical calculations and associated discussion for the test data reports
Supporting the CE-CERT Program Manager and Battelle in responding to any issues raised
in assessment reports and audits related to statistics and data reduction.
CE-CERT's QA/QC Manager (David Gemmill) for this verification test will:
Review the draft test/QA plan
Have responsibility for ensuring that the final test/QA plan is followed by CE-CERT staff in
all testing
Assist in the performance of technical systems audits, performance audits, and pre-test
facility reviews by the Battelle and EPA Quality Managers
Perform such audits and data reviews as are necessary to assure data quality in all
verification testing
Prepare and distribute an assessment report for each audit
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Verify implementation of any necessary corrective action
Issue a stop work order if internal audits indicate that data quality is being compromised;
notify CE-CERT Program Manager and Battelle if stop work order is issued
Provide a summary of the QA/QC activities and results for the test data report.
1.3.3 Vendors
Vendor representatives will:
Review the draft test/QA plan
Approve the final test/QA plan
Arrange with Battelle for performance of the test
Sign an AMS Center vendor agreement for the verification process, and pay a verification
fee that will partially cover the costs of the testing
Provide two identical portable analyzers for the duration of the verification test
Commit a trained technical representative to operate, maintain, and repair the portable
analyzers throughout the verification test
Participate in verification testing, including assisting in data acquisition for their analyzers
Review their respective draft ETV verification report and statement.
1.3.4 EPA
EPA's responsibilities in the AMS Center are based on the requirements stated in the
"Environmental Technology Verification Program Quality and Management Plan for the Pilot
Period (1995-2000)" (QAMP).(2) The roles of specific EPA staff under the QAMP are as
follows:
Ms. Elizabeth Betz is EPA's Quality Manager for the AMS Center. Ms. Betz will:
Review the draft test/QA plan
Perform, at EPA's option, one external technical systems audit during the verification test
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• Notify the Battelle AMS Center Manager to facilitate a stop work order if the external audit
indicates that data quality is being compromised
Prepare and distribute an assessment report summarizing results of any external audit
Review the draft verification reports and statements.
Mr. Robert Fuerst is EPA's AMS Center Manager. Mr. Fuerst will:
Review the draft test/QA plan
Approve the final test/QA plan
Review the draft ETV verification reports and statements
Oversee the EPA review process on the draft test/QA plan, reports, and verification
statements
Coordinate the submission of ETV verification reports and statements for final EPA
approval.
2.0 APPLICABILITY
2.1 Subject
This test/QA plan is applicable to the verification testing of portable analyzers for
determining gaseous concentrations of S02, CO, 02, NO, N02, and NOx, in controlled and
uncontrolled emissions from small combustion sources such as reciprocating engines,
combustion turbines, furnaces, boilers, and water heaters utilizing fuels such as natural gas,
propane, butane, coal, and fuel oils. The analyzers tested under this plan are commercial
devices, capable of being operated by a single person at multiple measurement locations in a
single day, using 110V AC electrical power or self-contained battery power. Although the size
and weight of the portable analyzers may vary considerably, the requirement for portability
generally implies a total weight of less than 50 pounds, size of about one cubic foot or less, and
minimal need for expendable supplies. The portable instrumental analyzers generally rely on
one or more of the following detection principles: 1) electrochemical (EC) sensors, 2)
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chemiluminescence emitted from the reaction of NO with ozone (03) produced within the
analyzer, 3) non-dispersive infrared (NDIR) absorption, 4) fluorescence detection, and/or 5)
ultraviolet (UV) absorption. The analyzers determine concentrations of S02, CO, and 02
directly. The analyzers may also determine NO and N02 (separately reporting NOx as the sum
of these species), or may determine total NOx directly. A sample conditioning inlet, generally
consisting of a means to cool and dry the sample gas stream, is often a standard component of
the analyzers.
Verification testing requires a reference for establishing the quantitative performance of
the tested technologies. In laboratory verification testing under this test/QA plan, the reference
will be EPA Protocol Gas Standards for S02, CO, 02, NO, and N02. For the combustion source
testing conducted under this test/QA plan, the reference will be measurements based on the
methods described in 40 CFR Part 60 Appendix A, i.e., EPA Methods 6C for S02, State of
California Air Resources Board (CARB) Method 100 for CO, EPA Method 3A for 02, and EPA
Method 7E for NOx. These methods are further described in Section 5.2.
This test/QA plan calls for the use of diverse small combustion sources during
verification testing. Other sources may be substituted, if they are more appropriate than those
specified for the analyzers undergoing testing.
2.2 Scope
The overall objective of the verification test described in this plan is to provide
quantitative verification of the performance of the portable analyzers in measuring gaseous
concentrations of S02, CO, 02, NO, N02, and/or NOx under realistic test conditions. The
portable analyzers are commonly used for combustion efficiency checks, spot checks of
pollution control equipment, and in periodic monitoring applications of source emissions. In
such applications the portable analyzers are used where a reference method, implemented as part
of a continuous emission monitoring (CEM) system, is not required. For these types of
applications, at least the following performance characteristics are generally expected:
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Relative accuracy within 20 percent relative to the reference method
Response time less than 4 minutes
In multipoint calibration, a linear slope between 0.98 and 1.02, and r2 greater than 0.9995
Span drift of no more than ±5 percent of the span gas value, based on zero/span checks
before and after source emissions measurements
Span drift of no more than ±1 percent of the span gas value for NO and no more than ±2
percent of the span gas value for S02, CO, 02 and N02, based on zero/span checks separated
by at least 12 hours with the analyzer turned off
Maximum span differences of ±3 percent for S02, CO, 02, NO and N02 resulting from
ambient temperature over a range of 55°F to 90°F
Sensitivities to potential interferents of no more than ±2 percent of range for CO, 02, and NO
and no more than ±3 percent of range for S02 and N02.
These performance characteristics have been incorporated in previous test protocols for
portable electrochemical analyzers.(e 8 •3) However, because the verification test specified herein
is intended to provide a quantitative performance assessment, not approval or a pass/fail
judgment relative to a criterion, these performance characteristics are not incorporated as criteria
in this test/QA plan. They are shown above merely to provide the reader with background on the
degree of performance that might be expected from the portable emission analyzers.
It is beyond the scope of this verification test to simulate the exposure history and aging
processes that may occur over the entire useful life of a portable analyzer. For example, it has
been established that electrochemical NO analyzers may exhibit drift that depends upon their
past history of use and the current ambient temperature. Furthermore, electrochemical analyzers
in general use interference rejection materials that may deteriorate with age. These long-term
changes in EC analyzers cannot be simulated in this verification test, however appropriate
quality assurance/quality control guidelines to account for such effects in use have been
published in EPA's Conditional Test Methods (CTM) -022 and -030.(4,5) Application of those
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guidelines is recommended to assure continued operation of EC analyzers at the levels of
performance established in this verification test.
3.0 DEFINITIONS
Accuracy - The degree of agreement of an analyzer's response with that of the reference
method, determined in simultaneous sampling of emissions from realistic combustion sources.
Ambient Temperature Effect - The dependence of an analyzer's response on the temperature
of the environment in which it is operating. A potential cause of span and zero drift.
Analyzer - The total equipment required for the determination of target gas concentrations, by
whatever analytical approach. The analyzer may consist of the following major subsystems:
1. Sample Conditioning Inlet. That portion of the analyzer used for one or more of the
following: sample acquisition, sample transport, sample conditioning, or protection of
the analyzer from the effects of the stack effluent, particulate matter, or condensed
moisture. Components may include filters, heated lines, a sampling probe, external
interference gas scrubbers, and a moisture removal system.
2. External Interference Gas Scrubber. A device located external to (e.g.) an
electrochemical cell, or other detector, and used to remove or neutralize compounds
likely to interfere with the selective operation of the detector.
3. Detector. That portion of an analyzer that senses the gas to be measured and generates
an output proportional to its concentration. The detection principle may be
electrochemical, chemiluminescent, NDIR, fluorescent, UV absorption, or other suitable
approaches.
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4. Moisture Removal System. Any device used to reduce the concentration of moisture
from the sample stream for the purpose of protecting the analyzer from the damaging
effects of condensation and corrosion, and/or for the purpose of minimizing errors in
readings caused by scrubbing of soluble gases. Such systems may function by cooling
the sample gas, or by drying it through permeation or other means.
5. Data Recorder. A strip chart recorder, computer, display, or digital recorder for
recording measurement data from the analyzer output. A digital data display may be
used when recording measurements manually.
Data Completeness - The ratio of the amount of S02, CO, 02, NO, N02, and/or NOx data
obtained from an analyzer to the maximum amount of data that could be obtained in a test.
Detection Limit - The true analyte concentration at which the average analyzer response equals
three times the standard deviation of the noise level when sampling zero gas. The detection limit
may be a function of the response time, which should be stated when the detection limit is cited.
Gas Dilution System - An instrument or apparatus equipped with mass flow controllers, capable
of flow control to ±1 percent accuracy, and used for dilution of span or interference gases to
concentrations suitable for testing of analyzers.
Fall Time - The amount of time required for the analyzer to achieve 95 percent response to a
step decrease in target gas concentration.
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Inter-Unit Repeatability - The extent to which two identical analyzers from a single vendor,
tested simultaneously, provide data that agree. The statistical definition of agreement may vary
depending on the test under consideration.
Interferences - Response of the analyzer to a constituent of the sample gas other than the target
analytes.
Interrupted Sampling - A test in which an analyzer is turned off for at least 12 hours, and its
performance is checked both before and after the interruption. This test assesses how well the
analyzer maintains its performance in the face of being turned on and off.
Linearity - The linear proportional relationship expected between analyte concentration and
analyzer response over the full measuring range of the analyzer.
Measurement Stability - The uniformity of an analyzer's response over time, assessed relative
to that of the reference method, during sampling of steady state emissions from a combustion
source. Stability over time periods of one hour or more is of interest.
Measuring Range - The range of concentrations over which each analyzer is designed to
operate. Several measuring ranges may be used in testing of any given analyzer, as long as
suitable zero and span checks are performed on the measuring ranges used.
Refresh Cycle - A period of sampling of fresh ambient air, required to maintain correct
operation of an EC analyzer by replenishing oxygen and moisture in the EC cell.
Response Time - The amount of time required for the analyzer to achieve 95 percent response to
a step change in target gas concentration.
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Rise Time - The amount of time required for the analyzer to achieve 95 percent response to a
step increase in target gas concentration.
Sample Flow Rate - The flow rate of the analyzer's internal sample pump under conditions of
zero head pressure.
Span Calibration - Adjustment of the analyzer's response to match the standard concentration
provided during a span check.
Span Check - Observing the response of the analyzer to a gas containing a standard
concentration of at least 90 percent of the upper limit of the analyzer's measuring range.
Span Drift - The extent to which an analyzer's reading on a span gas changes over time.
Span Gas - A known concentration of a target analyte in an appropriate diluent gas, e.g., NO in
oxygen-free nitrogen. EPA Protocol Gases are used as span gases in this verification test.
Zero Calibration - Adjustment of an analyzer's response to zero based upon sampling of high
purity gas (e.g., air or nitrogen) during a zero check.
Zero Check - Observing the response of the analyzer to gas containing no target analytes,
without adjustment of the analyzer's response. High purity nitrogen or air may be used as the
zero gas.
Zero Drift - The extent to which an analyzer's reading on zero gas changes over time.
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4.0 SITE DESCRIPTION
4.1 General Site Description
Verification testing under this test/QA plan will be conducted by Battelle, or by a test
facility with suitable capabilities and demonstrated experience under Battelle direction. The
initial test is planned to be conducted at CE-CERT's laboratory test facility, 1200 Columbia
Avenue, Riverside, California. Testing will be conducted in the CE-CERT Stationary Source
Emissions Research Chamber with well-characterized emission sources.
4.2 Site Operation
Laboratory and source testing will be conducted by CE-CERT staff, using equipment and
test facilities on hand. Commercial technologies being tested will be operated by vendor staff
during testing.
4.3 Emission Sources
The commercial technologies will be verified in part by sampling the emissions from
combustion sources, intended to provide emission concentration levels in the following three
ranges:
Low: S02 < 20 ppm, CO < 20 ppm; total NOx < 20 ppm
Medium: S02 200-500 ppm; CO 500-1000 ppm; total NOx 100-500 ppm
High: S02 > 900 ppm; CO > 1,900 ppm; total NOx > 1,000 ppm.
In addition, these combustion sources will produce 02 levels as low as <5%. Previously
characterized combustion sources will be used to provide these emission levels. Examples of
sources identified by CE-CERT are described in the following sections. Other sources may be
substituted as appropriate. Vendors may choose not to test their analyzers on sources or over
concentration ranges that are not appropriate to their analyzers.
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4.3.1 Commercial Range Burner Cooktop
A commercial natural gas-fired cooktop with four range burners will be used to generate
CO, 02, and NOx emissions in a wide range of concentrations. The cooktop can be operated with
any combination of one to four burners in operation. In addition, the firing rate of each burner
can be adjusted from 0 - 8,500 Btu per hour (0 - 8.5 Kbtu/hr). The cooktop has an overall
maximum firing rate of 34,000 Btu per hour (34 KBtu/hr). This appliance is capable of
generating 02 and NOx emissions of various concentrations as a function of the number of
burners operating and firing rates of each burner. Furthermore, CO concentrations can be
manipulated by adjusting the combustion air flow rate on individual burners. Emissions from
this source will be captured prior to measurement using a quartz collection dome designed
according to the Z21.1 specifications of the American National Standards Institute (ANSI).
4.3.2 Small Diesel-Fueled Engine
A portable diesel engine will be used to generate a wide range of S02 and NOx emissions
and 02 concentrations. The 5 Hp engine is of a type used in portable residential backup power
supplies. The engine is mounted to an eddy-current dynamometer so that engine load, and
consequently emission concentrations, may be varied over a wide range. The exhaust is ducted
into a dilution tunnel. The dilution ratio can be adjusted from zero to 200:1 using a positive
displacement (roots-type) blower with a variable frequency drive. By operating the engine
dynamometer at different loads, and adjusting the dilution ratio of exhaust gases, a wide range of
emissions concentrations can be generated. For example, the Hatz Model 1B20 engine produces
from about 75 to nearly 700 ppm NO,., depending on load. By varying dilution ratios and
timing, NOx emissions from 1 ppm to over 1,000 ppm can be generated. The diesel fuel used in
operating this generator will contain a high sulfur content in order to generate the required
concentrations of S02. A single batch of fuel sufficient for all tests will be obtained, so that fuel
composition will be constant during testing.
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4.4 Operation of Sources
Both combustion sources used will be operated according to the manufacturer's or
regulatory instructions, and with proper attention to safety requirements. Some specific factors
associated with the different sources are noted below.
4.4.1 Commercial Range Burner Cooktop
Installation of the range burner cooktop, the gas supply pressure regulators, and inlet and
outlet piping configurations, shall all be in accordance with the manufacturer's instructions. The
gas usage of the range burners over the test interval will be measured in cubic feet with a dry gas
meter or other flow monitoring device accurate to within about ±1 percent. The dry gas meter
reading will be corrected for gas pressure and temperature. The range top burner will be
operated at various conditions to generate the required emission concentrations. The burners
will be operated with the ANSI quartz collection dome and the standard loads in place. The
sample location will be a minimum of 8 duct diameters downstream of flow disturbances
(valves, reducers, elbows, etc.), and a minimum of 2 duct diameters upstream of the closest flow
disturbance (including end of duct or pipe open to atmosphere). Sampling of the exhaust stream
will take place at the center point of the flue vent.
Comparison of test data is facilitated by operating the device until steady-state conditions
are attained, before acquiring test data. Generally, steady-state can be defined by one or more of
the following conditions over a 15-minute interval:
Temperature changes in the center position of the exhaust of not more than +10°C;
• NOx changes at the center of the exhaust duct of not more than ±10 percent relative to the
mean over the 15 minute interval as determined using the EPA reference method (see
Section 5.2);
02 changes at the center of the exhaust duct of not more than + 0.50 percent absolute
(± 5,000 ppm) from the mean sampled over the 15 minute interval.
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4.4.2 Small Diesel-Fueled Engine
The diesel engine will be set up and operated in accordance with the manufacturer's
instructions. The engine will be mounted to a test stand and will be coupled with an eddy-
current dynamometer. The dynamometer controller will be used to set engine speed and load
conditions for testing. The exhaust from the generator will be horizontally discharged into a
dilution tunnel. The sample location will be a minimum of 8 duct diameters downstream of any
flow disturbance, and a minimum of 2 duct diameters upstream of the closest flow disturbance
(including end of duct or pipe open to atmosphere). Sampling of the exhaust streams will take
place at the center point of the dilution tunnel. The air/ fuel mixture, timing, load, and dilution
ratios will be checked and adjusted to the correct operation criteria and the target emission
concentrations. The device will be operated until steady-state conditions are approached, as
described in Section 4.4.1, before data collection for verification takes place.
5.0 EXPERIMENTAL DESIGN
5.1 General Description of Verification Test
The verification test will consist of laboratory and combustion source experiments. In all
experimental activities, two identical units of a portable emission analyzer will be operated side-
by-side, and the performance of each will be quantified individually, i.e., data from the two units
will not be pooled. One pair of analyzers from one vendor will undergo testing at a time, and
testing will take place on successive days, without interruption. Each analyzer will be verified
on its measurements of as many of the following parameters as are applicable: S02, CO, 02, NO,
N02, and NOx. Each analyzer will be verified independently of any other analyzers participating
in this verification test. That is, no intercomparison or ranking of the analyzers from different
vendors will be made at any time during the verification test. Data from different analyzers
tested will be segregated in the data acquisition and analysis processes. The performance of
each analyzer will be quantified on the basis of statistical procedures stated in Section 9 of this
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plan, and the respective verification results will be documented in a verification report that is
reviewed in draft form by the analyzer vendor.
5.2 Reference Methods
The reference method used for S02 in this verification test will be based on EPA Method
6C, "Determination of Sulfur Dioxide Emissions from Stationary Sources (Instrumental
Analyzer Procedure)." With this method, S02 in sample gas extracted from a stack is detected
by ultraviolet (UV) absorption, non-dispersive infrared (NDIR) absorption, or pulsed
fluorescence methods.
The reference method used for CO will be based on CARB Method 100, "Determination
of Gaseous Emission Concentrations from Stationary Sources (Instrumental Analyzer
Procedure)." With this method, CO in sample gas extracted from a stack is detected by NDIR.
The reference method used for 02 will be based on EPA Method 3A, "Determination of
Oxygen and Carbon Dioxide Concentrations in Emissions from Stationary Sources (Instrumental
Analyzer Procedure)" With this method, a portion of the sample gas extracted from a stack is
conveyed to instruments for 02 detection.
The reference method used for NO, N02, and NOx in this verification test will be based
on EPA Method 7E, "Determination of Nitrogen Oxides Emissions from Stationary Sources
(Instrumental Analyzer Procedure)". This method is set forth in 40 CFR Part 60, Appendix A.
With this method, NO in sample gas extracted from a stack is detected by chemiluminescence
resulting from its reaction with ozone, produced in excess within the analyzer. A heated
converter reduces N02 to NO for detection. While NO is detected directly, N02 is inferred by
the difference between the NO reading and the NOx (= NO + N02) reading obtained with the
heated converter. Modifications to Method 7E procedures may be used, based upon past
experience or common practice, provided those modifications are indicated in the test report.
For example, it is recommended that the EPA Approved Alternative Method for checking the
converter efficiency (i.e., using an N02 Protocol Gas) be employed.®
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5.3 Laboratory Tests
Initial tests will be performed in a laboratory setting, i.e., without the use of a combustion
source. The standard of comparison in the laboratory tests will be commercially obtained EPA
Protocol Gas standards for S02, CO, 02, NO, and N02. The laboratory tests to be performed, the
objective of each test, and the number of measurements to be made in each test are summarized
in Table 1. Procedures for performing these tests are specified in Section 7. Statistical
comparisons to be made with the data are specified in Section 9.
5.4 Combustion Source Tests
The combustion source tests to be performed, the objective of each test, and the number
of measurements to be made in each test are shown in Table 2. The tests listed in Table 2 will be
performed using two combustion sources. The standards of comparison in the combustion tests
will be based on EPA Methods 3 A, 6C, 7E, CARB Method 100, and in some cases response to
EPA Protocol Gases. Detailed procedures for conducting these tests are provided in Section 7.
Statistical comparisons to be made with the data are specified in Section 9.
5.5 Additional Performance Factors
In addition to the performance parameters listed in Tables 1 and 2, the following factors
will be verified using data from both the laboratory and combustion source tests. Other
operational features not yet identified may also become evident during the tests, and will be
evaluated.
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5.5.1 Inter-Unit Repeatability
No additional test activities will be required to assess the inter-unit repeatability of the
analyzers. This test will be based on comparisons of the simultaneous S02, CO, 02, NO, N02,
and/or NOx data obtained from the two analyzers from each vendor. Repeatability will be
assessed based on data from all laboratory and combustion source tests. Repeatability in each
type of test will be assessed separately.
Table 1. Summary of Laboratory Tests
Laboratory Test
Objective
Total Number of
Measurements'3' to be Used in
Verification
Linearity
Determine linearity of response over the
full measuring range
21
Detection Limit
Determine lowest concentration
measurable above background signal
9
Response Time
Determine time needed for analyzer to
respond to a change in target analyte
concentration
up to 60 (estimated)
Interferences
Determine analyzer response to species
other than target species
5
Ambient Temperature
Determine effect of ambient temperature
on analyzer zero and span
12
Interrupted Sampling
Determine effect on response of full
analyzer shutdown
4
Pressure
Sensitivity
Determine effect of duct pressure on
analyzer sample flow and response
9
(a) Number of separate measurements to be made in the indicated test, for each target analyte (S02,
CO, 02, NO, N02, or NOx).
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Table 2. Summary of Combustion Source Tests
Combustion
Source Test
Objective
Comparison
Based On
Total Number of
Measurements'3' to
be Used in
Verification
Accuracy
Determine degree of agreement
with Reference Method
Reference Method
45
Zero/Span Drift
Determine change in zero gas and
span gas response due to exposure
to combustion source emissions
Gas Standards
50b
Measurement
Stability
Determine the analyzer's ability to
sample combustion source
emissions for an extended time
Reference Method
60c
(a) Number of separate measurements to be made in the indicated test for each analyzer, for each
analyte (S02, CO, 02, NO, N02, or NOx).
(b) Augmented with 8 additional measurements from the Linearity and Ambient Measurement tests
(See Section 7.9).
(c) Data collected once per minute for one hour of measurement.
5.5.2 Data Completeness
No additional test activities will be required to determine the data completeness achieved
by the analyzers. Data completeness will be assessed based on the S02, CO, 02, NO, N02,
and/or NOx data recovered from each analyzer relative to the maximum amount of data that
could have been recovered.
5.5.3 Cost
Analyzer cost will be assessed in terms of the full purchase cost of the analyzer as used in
this verification test, i.e., including all accessories and sampling components. Cost information
will be provided by the vendors.
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5.6 Test Schedule
Verification testing will be conducted by performing the tests described above in a fixed
sequence. The analyzers provided by each vendor will undergo that full test sequence, one
vendor at a time. The sequence of testing activities is expected to take up to 6 days to complete.
An example schedule of those test days is shown in Table 3. The first four days are devoted to
laboratory testing, and the last two to source emissions testing. Testing of each vendor's
analyzers will take place on successive days, without interruption of the test sequence.
6.0 MATERIALS AND EQUIPMENT
6.1 Gases
6.1.1 EPA Protocol Gases
The span gases used for testing and calibration of S02, CO, 02, NO and N02 will be EPA
Protocol 1 Gases(7), obtained from a commercial supplier. These gases will be accompanied by a
certificate of analysis that includes the uncertainty of the analytical procedures used to confirm
the span gas concentration. Span gases will be obtained in concentrations that match or exceed
the highest measuring ranges of any analyzer to be tested, e.g., 2,000 ppm for S02; 4,000 ppm
for CO; 21% for 02; 4,000 ppm for NO; and 400 ppm for N02, are likely to be appropriate.
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Table 3. Schedule of Verification Testing Activities
Test Day
Approximate Time Period
Testing Activity
One
0800-1300
Vendor checks and prepares analyzers for
testing.
1300-1700
Begin linearity test, including detection limit
and response time determinations.
Two
0800-1200
Continue linearity test, including detection
limit and response time determinations.
1300-1700
Complete linearity test.
1700-Overnight
Begin interrupted sampling test.
Three
0800-0900
Complete interrupted sampling test.
0900-1200
Interference test.
1300-1700
Pressure sensitivity test.
Four
0800-1200
Begin ambient temperature test.
1300-1700
Complete ambient temperature test.
Five
0800-1200
Begin relative accuracy test with range burner
cooktop, including Zero/Span Drift Test.
1300-1700
Complete relative accuracy test with range
burner cooktop, including Zero/Span Drift Test.
Six
0800-1200
Begin relative accuracy test with diesel engine,
including Zero/Span Drift Test.
1300-1700
Complete relative accuracy test with diesel
engine, including Zero/Span Drift Test.
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6.1.2 Interference Gases
Compressed gas standards for use in testing interference effects will be obtained from a
commercial supplier. These gases must be gravimetrically prepared, and must be certified
standards with a preparation accuracy (relative to the nominal target concentration) within
±10%, and an analytical accuracy (i.e., confirmation of the actual standard concentration by the
supplier) within ±2%. Each interference gas must be accompanied by a certificate indicating
the analytical results and the uncertainty of the analytical procedures used to confirm the
concentration. Each interference gas will contain a single interferent in a matrix of high purity
air or nitrogen. The interference gas concentrations will be approximately: C02, 5 percent; H2,
100 ppm; NH3, 500 ppm; and hydrocarbons, approximately 500 ppm methane, 100 ppm C2
compounds, and 50 ppm total C3 and C4 compounds. The S02, NO, and N02 Protocol Gases will
be used for interference testing of those species.
6.1.3 High Purity Nitrogen/Air
The high purity gases used for zeroing of the reference methods and the commercial
analyzers, and for dilution of EPA Protocol gases and interference gases, must be air or nitrogen,
designated by the supplier as CEM Grade, Acid Rain CEM Zero Gas, or comparable.
A certificate of gas composition will be obtained from the supplier confirming the quality
of the gas.
6.2 Reference Instruments
S02 reference measurements will be performed based on EPA Method 6C using a
commercially available ultraviolet (UV) monitor. CO reference measurements will be
performed based on CARB Method 100 using a commercially available non-dispersive infrared
(NDIR) monitor. 02 reference measurements will be performed based on EPA Method 3 A using
a commercially available monitor employing paramagnetic pressure detection. NO and NOx
reference measurements will be performed based on EPA Method 7E using commercially
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available chemiluminescent monitors. The monitors used must have measurement ranges
suitable for the variety of combustion sources to be used; e.g., ranges from less than 10 ppm to
over 1,000 ppm full scale [1% - 25% for 02] are desirable. The calibration procedures for these
monitors for this test are described in Section 8.1.1.
6.3 Dilution System
The dilution system used for preparation of calibration gas mixtures must have mass flow
control capabilities for both dilution gas and span gas flows. The dilution system may be
commercially produced or assembled from separate commercial components. It must be capable
of accepting a flow of compressed gas standard and diluting it over a wide range with high purity
nitrogen or air. Dilution factors ranging from about 4:5 to about 1/100 are required; a dilution
factor of up to 1:1000 is desirable. Calibration of the dilution system before the test is described
in Section 8.1.2.
6.4 Temperature Sensors
The sensor used to monitor temperature in the exhaust stack or duct during experiments
on combustion source emissions must be a thermocouple equipped with a digital readout device.
The thermometers used for measurement of room or chamber air temperature may be of the
mercury-in-glass, thermocouple, or other types, as long as they provide an accuracy within
approximately ±1°F as determined through pre-test calibration. Calibration requirements for
temperature measurements are presented in Section 8.1.3.
6.5 Gas Flow Meters
The natural gas flow to the gas burner and water heater must be monitored during use
with a dry gas meter and associated readout device. Dry gas meter readings will be corrected for
temperature and pressure.
Rotameters, automated bubble flow meters, or other devices capable of indicating the
analyzer flow rate within ±5 percent will be used in tests of the flow rate stability of the
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analyzers (Section 7.7). Certification of flow rate precision should be obtained from the
supplier. Calibration requirements for flow rate measurements are presented in Section 8.1.4.
7.0 TEST PROCEDURES
In this section the specific procedures to be used in the verification test are specified.
Each vendor's analyzers (i.e., two identical units) will be subjected to this test procedure
simultaneously. However, only one vendor's analyzers will undergo testing at one time. The
schedule and sequence of testing are specified in Section 5.6 above. As noted previously, this
verification test cannot address analyzer behavior that occurs after an extended exposure history,
or because of changes in the analyzer itself due to long term use.
In some of the verification test procedures, a relatively small number of data points will
be obtained to evaluate performance. For example, response times (i.e., rise and fall time) will
be determined based on a single trial, albeit by means of recording several successive readings.
Similarly, zero/span drift, temperature and flow effects, etc., will be verified based on a few
comparisons of average values determined over short time periods. The quantity of data
obtained in this verification test exceeds that obtained in comparable test procedures;(e 8 •3)
however, in some cases the data obtained will be sufficient to determine the average value, but
not the precision, of the verification result. Tests for which that is the case are identified
appropriately in Section 9.
Note: Electrochemical analyzers undergoing testing may require refresh cycles of
ambient air sampling to maintain proper operation. This requirement may be particularly
important in sampling of dry high purity gases, as in the laboratory tests outlined below.
The operators of such analyzers may perform refresh cycles at any time during the test
procedures; however, no part of any test procedure will be replaced or eliminated by
performance of a refresh cycle.
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7.1 Linearity
Linearity of the analyzers will be verified in the laboratory by establishing multi-point
calibration curves. Separate curves will be established for S02, CO, 02, NO, and N02 on each
analyzer. Calibration points will be run at zero concentration, and at target emission
concentrations approximating 10, 20, 40, 70, and 100 percent of the analyzer's nominal full-
scale measuring range for each component. The zero point will be sampled six times, and other
calibration points three times, for a total of 21 calibration points each for S02, CO, 02, NO, and
N02.
General procedures for the Linearity Test are:
1. Set up the gas dilution system to provide calibration gases by dilution of an EPA Protocol
gas standard for a gas of interest (S02, CO, 02, NO, or N02).
2. Determine the response curve for each individual component on a single vendor's
analyzers by the procedure specified below. The two analyzers from each vendor will be
tested simultaneously but independently, i.e., no averaging of results from the two
analyzers will be done.
The specific test procedure is:
1. Perform a zero and span calibration for each component on the analyzers to be tested.
Make no further adjustments to the zero or span settings of the analyzers once the
Linearity Test has begun.
2. Provide a sample flow of the pure diluent gas to the analyzers, and record the readings.
3. Provide a flow of a span gas concentration approximately equal to the upper limit of the
nominal measuring range of the analyzers, and record the readings.
4. Using the gas dilution system to change the gas concentration as appropriate, determine
the response to additional concentration points at zero, 10, 20, 40, 70, and 100 percent of
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the nominal measuring range. After every three points, provide pure dilution gas and
record the analyzers' readings again.
5. The order of obtaining the concentration points in steps 2 to 4 will be as follows: Zero,
100%, 10%, 40%, zero, 70%, 20%, 10%, zero, 20%, 40%, 70%, zero, 100%, 70%, 40%,
zero, 20%), 10%, 100%, zero.
6. At each concentration point, record all responses of the analyzers (i.e., S02, CO, 02, NO,
N02, and/orNOx).
7. In the course of the Linearity Test, conduct the Response Time Test as described in
Section 7.3.
8. Repeat steps 2 through 7 as needed to complete the Linearity and Response Time tests
for all target analytes (S02, CO, 02, NO, and N02).
9. At the completion of steps 2 through 7 for each analyte, a final zero and span check for
that analyte may be conducted. Alternatively the final two data points of the linearity test
(100%) and zero) may be recorded as the final span and zero check readings.
7.2 Response Time
The rise and fall times of the analyzers will be established in the laboratory by
monitoring the response of the analyzers during the fifth, sixth, and seventh data points (i.e.,
zero, 70 percent, and 20 percent of scale, respectively) in the Linearity Test (Section 7.1). The
following procedures will be followed:
1. Determine the analyzer's response at the zero level using pure diluent gas.
2. Switch to a calibration gas that is approximately 70 percent of the analyzer's
measurement range.
3. Record the analyzer's response at 10-second intervals, until 60 such readings have been
recorded or until a stable response to the calibration gas is achieved.
4. Switch to a calibration gas that is approximately 20 percent of the analyzer's
measurement range.
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5. Again record the analyzer's response at 10-second intervals, until 60 such readings have
been recorded or until a stable response is achieved.
6. Determine the elapsed time required for the analyzer to reach 95 percent of its final stable
response after switching from diluent gas to the 70 percent calibration gas (rise time), and
from the 70 percent calibration gas to the 20 percent calibration gas (fall time).
7. Perform this test using S02, CO, 02, NO and N02, as part of the Linearity Test, by using
the fifth, sixth and seventh data points of the Linearity Test as described above.
7.3 Detection Limit
The detection limits of each analyzer for each analyte will be verified based on the data
obtained at zero concentration (six data points) and at the lowest calibration point (three data
points) in the Linearity Test (Section 7.1). No additional experimental activities will be
conducted. Detection limits will be determined separately for S02, CO, 02, NO, N02, and/or
NOx, as described in Section 9.2.3.
7.4 Interferences
The effect of interferences will be established by supplying the analyzers with test gases
containing potential interferents at known concentrations, and monitoring the analyzers'
response. The interferents compounds to be tested, the test concentrations, and the target
analytes to be evaluated for possible interference are specified in Table 4. Cross-sensitivity of
the analyzers to S02, CO, 02, NO, and N02 will be assessed by means of the Linearity Test data,
rather than by additional interference testing. Interference testing will include a test of response
to S02 and NO present at the same time; this test particularly targets electrochemical NO
sensors, which can be affected by the reaction of S02 with N02 (formed as a product of the
sensor's oxidation of NO in the detection process).
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Table
. Summary of Interference Tests to
)e Performed
Interferent
Interferent Concentration
Target Analyte
O
O
5%
S02, NO, N02, NO,, CO, 02
H2
100 ppm
CO
nh3
500 ppm
NO, N02, NOx
Hydrocarbon Mixture1-3-1
-500 ppm Q, -100 ppm C2,
-50 ppm C3, and C4
S02, NO, N02, NO,, CO, 02
S02 and NO together
-400 ppm each
S02, NO, N02, NOx
(a) C, = methane, C2 = ethane + ethylene, etc.
The stepwise procedure for conducting the Interference Test is as follows:
1. Zero the analyzer with high purity diluent gas (air or nitrogen), and record the readings
for all target analytes (S02, CO, 02, NO, N02, and/or NO,).
2. Supply a potential interferent gas to the analyzer, diluted if necessary to the
concentrations shown in Table 4.
3. Allow the analyzers to stabilize in sampling of the interferent gas, and again record the
responses to all the pertinent target analytes (S02, CO, 02, NO, N02, and/orNOx).
4. Repeat steps 1 to 3 for the entire set of potential interferents.
The results of this test will be up to 30 total measurements of interference response for
each analyzer (i.e., readings for the six target analytes for each of the five interferants listed in
Table 4). Each measurement of interference response consists of the difference in readings
between zero gas and the same diluent gas containing the interferant gas.
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7.5 Ambient Temperature
The effect of ambient temperature on analyzer operation will be evaluated by comparing
the response of the analyzer in the laboratory at room temperature, to that in test chambers at
both elevated and reduced temperatures. Procedures for this test are as follows:
1. Record the room temperature and actual chamber temperatures during any data collection
period.
2. Perform a zero check, a single point span check with S02, CO, 02, NO and N02, and
another zero check on both analyzers in the laboratory at room temperature. Record the
zero and span gas readings. Make no adjustments to the analyzers' zero or span settings
after this point.
3. Place both analyzers together in a laboratory test chamber, which is heated to 105°F
(±5°F).
4. Allow one hour in the heated chamber for temperature equilibration. Record the chamber
temperature, perform a zero check, a span check, and another zero check, and record the
readings.
5. Remove the analyzers from the heated chamber and place them together in an adjacent
chamber cooled to 45°F (±5°F).
6. Allow one hour in the cooled chamber for temperature equilibration. Record the
chamber temperature, perform a zero check, a span check, and another zero check, and
record the readings.
7. Remove the analyzers from the cooled chamber and allow them to warm to room
temperature. Perform a zero check, a span check, and another zero check, and record the
readings.
The results of the Ambient Temperature Test will be 12 total data points (2 zero and 1
span at each stable temperature condition) for each target analyte.
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7.6 Interrupted Sampling
The effect of interrupted sampling on the analyzers will be assessed in the laboratory by
turning the analyzers off at the end of the second test day, i.e., after the Linearity Test (Section
7.1). The results of a zero and span check conducted at the end of that day will be compared to
results of a similar check when the analyzers are powered up after a shutdown. Specific
procedures for this test are:
1. Upon completion of the second test day, shut off all power to the analyzer.
2. After at least 12 hours, restore power to the analyzer. Make no adjustments of any kind
to the analyzers.
3. Once the analyzer has stabilized (as indicated by internal diagnostics or operator
observations), perform a zero and span check for S02, CO, 02, NO, and N02, using the
same span concentrations used before the shutdown.
4. Record the readings and compare them to those obtained before the shutdown period.
The readings consist of four data points (zero/span before shutdown and zero/span after
shutdown) for each target analyte.
7.7 Pressure Sensitivity
The Pressure Sensitivity test will evaluate the ability of an analyzer to maintain a
constant sample flow rate in the face of small positive or negative static pressure in the sample
duct (relative to atmospheric pressure), and to maintain constant response to S02, CO, 02, NO,
and N02 under such conditions. This sensitivity will be tested in the laboratory by sampling
from a flow of calibration gas, and monitoring the dependence of the analyzer's response and
sample flow rate on the pressure of the calibration gas. The stepwise procedure is as follows:
1. Prepare a sampling manifold capable of providing sample flow to the analyzers at
pressures (relative to the ambient atmosphere) ranging between +10 and -10 inches of
water.
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2. Insert a flow measuring device (automated bubble flow meter, rotameter or other non-
restrictive type) in the sample inlet flow to each analyzer.
3. Supply the manifold with zero gas at a pressure equal to that of the ambient atmosphere.
Measure the analyzer's inlet flow rate while sampling from the manifold.
4. Repeat step 3 at a pressure of+10 inches of water, and again at a pressure of -10 inches
of water, relative to the ambient atmosphere.
5. Remove the flow meter from the inlet line of the analyzer, reconnect the analyzer to the
manifold, adjust the manifold pressure to equal the ambient atmospheric pressure, and
record the analyzer's response to the zero gas.
6. Supply the manifold with S02 at a concentration approximately equal to 60 percent of the
analyzer's measuring range. Record the analyzer's response.
7. Again supply the manifold with zero gas and record the analyzer's response.
8. Repeat steps 5 to 7 with zero gas and the same span gas concentration at a pressure of
+10 inches of water, relative to the ambient atmosphere, and again at a pressure of -10
inches of water, relative to the ambient atmosphere.
9. Repeat steps 5 to 8 with CO.
10. Repeat steps 5 to 8 with 02.
11. Repeat steps 5 to 8 with NO.
12. Repeat steps 5 to 8 with N02.
The results of this test are nine total data points (2 zero and 1 span at each of three
pressure conditions) for each target analyte.
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7.8 Accuracy
Accuracy relative to reference method results will be verified by simultaneously
monitoring the emissions from combustion sources with the reference method and with two units
of the analyzer being tested. It is recommended that data be taken during steady state operation
of the sources; diesel engine emissions will be varied by altering the load placed on the engine.
Specific procedures to verily accuracy on each combustion source are:
1. Perform a zero and span check for S02, CO, 02, NO, and N02 on each analyzer being
tested, and on the reference method. Use span concentrations similar to the emission
levels expected from the combustion source being used. Do not recalibrate or adjust the
analyzers in the remainder of the test (the sample conditioning system may be cleaned or
changed if necessary, as long as the time and nature of the modification is noted in the
verification report).
2. Place sampling probes for the analyzers and reference method at the cross-sectional
midpoint of the source exhaust stack.
3. Once the readings have stabilized, record the S02, CO, 02, NO, N02, and/or NOx
readings of the commercial and reference analyzers.
4. Switch the sampling probes for the analyzers being tested to sample ambient air until
stable readings are obtained.
5. Return the sample probes to the stack and repeat steps 2 to 4 until a total of nine source
sampling intervals have been conducted, separated by periods of ambient air sampling.
6. Conduct the procedure above on both sources. Repeat the test procedure at one or more
separate operating, load, or engine RPM conditions. The planned number of
measurements to be made is listed in Table 5.
7. For one load condition with a diesel engine, conduct an extended sampling interval in
place of the last of the nine sampling periods (see Table 5). See Section 7.10 regarding
the performance of this procedure.
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8. Perform a zero and span check for each component on each analyzer after completing all
sampling from each source, before proceeding to sampling from the next source. For
each source, use the same span gas concentration as in the zero and span check
performed before source sampling.
Table 5. Summary of Data to be Collected for Accuracy Determination in the
Combustion Source Tests
Combustion Source
Number of
Source Operating
Conditions
Number of Sampling
Periods per Source
Operating Condition
Total Number of
Measurements to be
Collected for Each
Analyze^3'
Range Burner
Cooktop
2
9
18
Diesel Engine(b)
3 (e.g.)
9(c)
27(e.g.)
(a) Number of separate measurements of source emissions to be made for each target
analyte, i.e., S02, CO, 02, NO, N02, and/orNOx.
(b) For sake of example, three separate diesel operating conditions are assumed.
(c) At one condition, an extended sampling period will replace one measurement period (see
Section 7.10).
7.9 Zero/Span Drift
Zero drift and span drift will be evaluated using data generated in the Linearity,
Interrupted Sampling, and Ambient Temperature Tests in the laboratory, and the Accuracy Test
on combustion sources. No additional experimental activities are necessary. In the combustion
source tests, a zero and span check will be performed for S02, CO, 02, NO, and N02 on each
analyzer before sampling of the emissions from each source, and then again after the source
emissions measurements are completed (steps 1 and 8 of the Accuracy Test, Section 7.8). The
zero and span drift are determined as the difference in response on zero and span gases in these
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two checks. This comparison will be made for each analyzer, for all components, for both zero
and span response, using data from all five planned combustion source test conditions (Table 5)
(i.e., 10 zero and 10 span points for each component). In the laboratory, zero and span values
determined at the start and end of the Linearity and Ambient Temperature Tests will be similarly
compared, producing 4 more zero and 4 more span points for each species. The Interrupted
Sampling Test provides a distinct and independent measure of analyzer drift (zero and span
before shutdown and after re-start) (Section 7.6).
7.10 Measurement Stability
Stability in source sampling will also be evaluated in conjunction with the Accuracy Test
(Section 7.8). At one load condition during sampling of a diesel engine, each analyzer will
sample the emissions for a full hour continuously. A total of 60 minutes of data will be collected
as a continuous one-hour period. Data will be collected at one minute intervals from both the
reference monitor and the commercial analyzers. Stability will be assessed based on the
uniformity over time of the analyzers' response, with any instability of source output normalized
by means of the reference method data.
8.0 QUALITY ASSURANCE/QUALITY CONTROL
8.1 Instrument Calibration and Frequency
8.1.1 Reference Method Monitors
The monitors to be used for 02, NO,., S02, and CO reference measurements will be
subjected to a 4-point calibration with span gas prior to the first day of verification testing, on
each measurement range to be used for verification. For each sensor, one of the calibration
points will be zero gas; the other three calibration points will be approximately 30, 60, and 100
percent of the full scale measuring range. The N02 calibration will be pursuant to EPA ALT-
013 ,(6) The calibration error requirement will be consistent with that in Section 4.1 of Method
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6C, 40 CFR Part 60 Appendix A, i.e. the average response at each calibration point will differ
from that predicted by the linear regression to all the data points by less than 2 percent of the
instrument's measuring range. On each day of verification testing, each reference monitor will
undergo a zero and span check in the morning before the start of testing, and again after all
testing is completed for the day.
8.1.2 Gas Dilution System
Flow measurement or control devices in the dilution system will be calibrated prior to the
start of the verification test by means of a calibrated manual or automated soap bubble flow
meter. Corrections will be applied as necessary to the bubble meter data for temperature,
pressure, and water content.
8.1.3 Temperature Sensor/Thermometers
The thermocouple sensor used to determine source emission temperatures, and the
thermometers used to measure room or chamber temperatures, must have been calibrated against
a certified temperature measurement standard within the six months preceding the verification
test. At least once during this verification test each source temperature measurement device
must also be checked for accuracy as specified in Section 4.2 of Method 2A, 40 CFR Part 60
Appendix A, i.e., by comparison to an American Society for Testing and Materials (ASTM)
mercury-in-glass reference thermometer. That comparison must be done at ambient
temperature; agreement within ±2 percent in absolute temperature is required.
8.1.4 Gas Flow Meters
The dry gas meter must have been calibrated against a volumetric standard within the six
months preceding the verification test. In addition, at least once during this verification test the
meter calibration must be checked against a reference meter according to the procedure
described in Section 4.1 of Method 2A, 40 CFR Part 60 Appendix A.
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In addition, any other gas flow devices (e.g., rotameters) used in the verification must
have been compared to an independent flow measurement device within the six months
preceding the verification test.
8.2 Assessments and Audits
8.2.1 Pre-Test Laboratory Assessment
If the testing activities are performed by a test facility other than Battelle, Battelle will
assess the facility's capabilities for performing the test and meeting the quality requirements of
this test/QA plan prior to initiation of the test. Battelle will request that the test facility provide
their laboratory Quality Management Plan (QMP), related internal standard operating procedures
(SOPs), any certification records, training records, calibration records, and any other documents
Battelle deems necessary to ensure that the test facility has the appropriate operational
procedures to ensure a high level of quality.
8.2.2 Technical Systems Audits
Battelle's Quality Manager will perform a technical systems audit (TSA) once during the
performance of this verification test. The purpose of this TSA is to ensure that the verification
test is being performed in accordance with this test/QA plan, the Battelle AMS Center QMP,(1)
and all associated methods and SOP's. In this audit, the Battelle Quality Manager will review
the calibration sources and reference methods used, compare actual test procedures to those
specified in this plan, and review data acquisition and handling procedures.
At EPA's discretion, EPA QA/QC staff may also conduct an independent TSA of the
verification test. In any case, EPA QA/QC staff will review Battelle's TSA report, and provide
comments on the findings and actions presented in that report.
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8.2.3 Performance Evaluation Audit
A performance evaluation (PE) audit will be conducted by Battelle to assess the quality
of the measurements made in this verification test. This audit addresses only those
measurements made in conducting the verification test, i.e., the analyzers being verified and the
vendors operating these analyzers are not the subject of the performance evaluation audit. This
audit will be performed by analyzing a standard or comparing to a reference that is independent
of standards used during the testing. This audit will be performed once during the verification
procedure, using audit standards or reference measurements supplied by Battelle. The audit
procedures, which are listed in Table 6, will be performed under Battelle supervision by the
technical staff responsible for the measurements being audited.
Table 6. Summary of Performance Audit Procedures'^
Measurement to be Audited
Audit Procedure
Reference methods for S02, CO, 02, NO,
NOx
Analyze independent standards (i.e., obtained
from a different vendor)
Temperature
Compare to independent temperature
measurement
Gas Flow Rate
Compare to independent flow measurement
(a) Each audit procedure will be performed once during the verification test.
The PE audit for the reference methods will consist of analyzing a set of certified gas
standards provided by Battelle, for comparison to the corresponding standards used in the
verification test. The standards to be provided by Battelle will be obtained from a different
supplier than those used in the verification, and will have nominal concentrations similar to the
standards against which they will be compared. Agreement within 5% or within the combined
uncertainty of the two standards, whichever is greater, is expected. The PE audit of the
temperature and flow rate measurements will consist of a side-by-side comparison between the
measurement devices used in the verification test and independent devices provided by Battelle.
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Agreement of flow measurements within 5%, and of temperature readings within 2% in absolute
temperature, is expected. Performance audit results that do not meet these criteria for agreement
will trigger a repeat of the audit procedure. If agreement is not found in the repeated audit, the
disagreement will be noted and the pertinent measurement data will be flagged in the verification
report.
8.2.4 Data Quality Audits
The Battelle Quality Manager will audit at least 10 percent of the verification data
acquired in the verification test. The Battelle Quality Manager will trace the data from initial
acquisition, through reduction and statistical comparisons, and to final reporting.
8.3 Assessment Reports
Each assessment and audit will be documented in accordance with Sections 3.2.1 and
3.3.4 of the QMP for the AMS Center.(1) Assessment reports will include the following:
Identification of any adverse findings or potential problems
Space for response to adverse findings or potential problems
Possible recommendations for resolving problems
Citation of any noteworthy practices that may be of use to others
Confirmation that solutions have been implemented and are effective.
8.4 Corrective Actions
The Battelle Quality Manager during the course of any assessment or audit will identify
to the technical staff performing experimental activities any immediate corrective action that
should be taken. If serious quality problems exist, the Battelle Quality Manager is authorized to
stop work. Once the assessment report has been prepared, the Battelle Verification Testing
Leader, working with the test facility as necessary, will ensure that a response is provided for
each adverse finding or potential problem, and will implement any necessary follow-up
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corrective action. The Battelle Quality Manager will ensure that follow-up corrective action has
been taken.
9.0 DATA ANALYSIS AND REPORTING
9.1 Data Acquisition
Data acquisition in this verification test includes recording of the response data from the
analyzers undergoing testing, recording of data from the reference method analyzers, and
recording of operational data such as combustion source conditions, test temperatures,
calibration information, the times of test activities, etc.
Data acquisition for the commercial analyzers undergoing verification is primarily
performed by the vendors themselves during the laboratory tests. Each analyzer must have some
form of a data acquisition device, such as a digital display whose readings can be recorded
manually, a printout of analyzer response, or an electronic data recorder that stores individual
analyzer readings. In all laboratory tests the vendor will be responsible for reporting the
response of the analyzer to the sample matrices provided. In most laboratory tests, the analyzer
response to be reported will be in the form of an average or stable reading. However, in the
Response Time test the response will be reported as individual readings obtained at 10-second
intervals.
In general, data acquisition for the commercial analyzers and reference monitors must be
simultaneous during the combustion source tests in order to properly compare the two methods.
For all commercial analyzers that can produce an analog or digital electronic output, a data
acquisition system will be used to record both the commercial analyzer and reference monitor
responses during these tests. Data acquisition for the Zero/Span Drift Test will be based on
average or stable responses, similar to that for most of the laboratory tests, as noted above. For
analyzers that provide only visual or printed output, data will be recorded manually and
simultaneously for both the analyzers being tested and the reference monitor, using forms
provided for this purpose.
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Other data will be recorded in laboratory record books maintained by each staff member
involved in the testing. These records will be reviewed on a daily basis by test facility staff to
identify and resolve any inconsistencies. All data entered in record books or on test data sheets
must be entered directly, promptly, and legibly. All entries must be made in ink, and each page
or data sheet must be signed and dated by the person making the entry. Changes or corrections
to data must be made by drawing a single line through the error, initialing and dating the
correction, and adding a short explanation for any non-obvious error corrections.
In all cases, strict confidentiality of data from each vendor's analyzers, and strict
separation of data from different analyzers, will be maintained. This will be accomplished in
part by the separation in time between the conduct of each test on different analyzers. More
importantly, separate files (including manual records, printouts, and/or electronic data files) will
be kept for each analyzer. At no time during verification testing will staff engage in any
comparison or discussion of test data or of different analyzers.
Table 7 summarizes the types of data to be recorded; how, how often, and by whom the
recording is made; and the disposition or subsequent processing of the data. The general
approach is to record all test information immediately and in a consistent format throughout all
tests. Data recorded by the vendors are to be turned over to testing staff immediately upon
completion of the test procedure. Test records will then be converted to Excel spreadsheet files
by the same staff who conducted the verification tests. Identical file formats will be used for the
data from all analyzers tested, to assure uniformity of data treatment. Separate data files will be
kept for each of the two identical analyzers provided by each vendor, to assure separation of data
and facilitate intercomparisons of the two units. This process of data recording and compiling
will be overseen by the test facility supervisor, i.e., the CE-CERT Program Manager or Battelle
Verification Testing Leader.
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Table 7. Summary of Data Recording Process for the Verification Test
Data to be
Recorded
Responsible
Party
Where Recorded
How Often
Recorded
Disposition of Data
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9.2 Statistical Calculations
The analyzer performance characteristics are quantified on the basis of statistical
comparisons of the test data. This process begins with conversion of the spreadsheet files that
result from the data acquisition process (Section 9.1) into data files suitable for evaluation with
SAS statistical software. The following are the statistical procedures used to make those
comparisons.
9.2.1 Linearity
Linearity will be assessed by linear regression with the calibration concentration as
independent variable and the analyzer response as dependent variable. A separate calibration
will be carried out for each unit. The calibration model is:
Yc = H(c) + error c
where Yc is the analyzer's response to a challenge concentration c, h(c) is a linear calibration
curve, and the error term is assumed to be normally distributed. If the variability is not constant
throughout the range of concentrations then weighting in the linear regression is appropriate. It
is often the case that the variability increases proportionally with the true concentration. The
variability (a) of the measured concentration values (c) may be modeled by the following
relationship:
CJ 2C = a + k CP
where a, k and p are constants to be estimated from the data. After determining the relationship
between the mean and variability, appropriate weighting will be determined such as
weight = wc = ~~~7
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The form of the regression model to be fitted is h(c) = + afk. Concentration values will be
calculated from the estimated calibration curve using the formula
c= h"1(Yc) = (Yc-a0)/ag
A test for departure from linearity may be carried out by comparing the residual sum of squares
6
X (YCi -cco-aid) nc,wa
i=l
to a chi-square distribution with 6-2 = 4 degrees of freedom. (nc is the number of replicates at
concentration c).
9.2.2 Response Time
The response time of the analyzers to a step change in analyte concentration is calculated by
determining the total change in response due to the step change (either increase or decrease) in
concentration, and then determining the point in time when 95 percent of that change was
achieved. Both rise and fall time will be determined. Using data taken every 10 seconds, the
following calculation is done:
Total Response = R, - R,,
where R, is the final response of the analyzer to the test gas after the step change and Rt, is the
final response of the analyzer before the step change. The analyzer response that indicates the
response time then is:
ResponseRT = 0.95(Total Response)
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The point in time at which this response occurs is determined by inspection of the
response/time data, and the response time is then calculated as:
RT = Time95% - Time,,
where Time95% is the time at which Response^ occurs and Time, is the time at which the step
change in concentration was imposed. Since only one determination will be made, the precision
of the rise and fall time results cannot be estimated.
9.2.3 Detection Limit
The detection limit (LOD) will be defined as the smallest true concentration at which the
analyzer's expected response exceeds the calibration curve at zero concentration by three times
the standard deviation of the analyzer's zero reading, i.e., «~+ 3 o0. The LOD may then be
determined by:
LOD = [(a[}f3o0) - a[]]/aP= 3o0/aP
where o0 is the estimated standard deviation at zero concentration.
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9.2.4 Interferences
The extent of interference will be reported in terms of the absolute response of the
analyzer to the interferant, and will be calculated in terms of the sensitivity of the analyzer to the
interfering species, relative to its sensitivity to S02, CO, 02, NO or N02. The relative sensitivity
is calculated as the ratio of the observed response of the analyzer to the actual concentration of
the interferent. For example, an analyzer that measures NO is challenged with 500 ppm of CO,
resulting in a difference in NO reading of 1 ppm. The relative sensitivity of the NO analyzer to
CO is thus 1 ppm/500 ppm = 0.2 percent. The precision of the interference results cannot be
estimated from the data obtained, since only one measurement is made for each interferent.
9.2.5 Ambient Temperature Effect
The analyzer response data obtained from a single point span check or a zero check at a
given temperature and a given concentration (i.e., zero or span) are not statistically independent.
Therefore, the average value in each sampling period will be used as a single value in the
comparison. Thus at room temperature, low temperature, and high temperature there will be two
data points for each analyzer, namely the average response on zero gas and the average response
on span gas, for each target analyte. Variability for low and for high temperatures will be
assumed to be the same as the variability at room temperature, and the variability determined in
the Linearity Test will be used for this analysis. The presence of an ambient temperature effect
on zero and span readings will then be assessed by trend analysis for response with temperature,
using separate linear regression analyses for the zero and for the span data.
9.2.6 Interrupted Sampling
The effect of interrupted sampling will be assessed as the arithmetic difference between zero
data and between span data obtained before and after the test. Differences will be stated in ppm
units. No estimate can be made of the precision of the observed differences.
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9.2.7 Pressure Sensitivity
The statistical analysis for evaluation of flow rate effects will be similar to that used for
assessing the ambient temperature effect. The analyzer response data at a given duct pressure
and a given concentration (i.e., zero or span) are not statistically independent; therefore the
average value in each sampling period will be used in the comparison. Thus at each of ambient
pressure, reduced pressure, and increased pressure there will be three total data points for each
analyzer, namely the analyzer flow rate and average response on zero gas and the average
response on span gas. Variability for reduced and increased pressures will be assumed to be the
same as the variability at ambient pressure, and the variability determined in the Linearity Test
will be used for this analysis. The presence of a duct pressure effect on analyzer flow rates and
response will then be assessed by separate linear regression trend analyses for flow rate, and for
response. The trend analysis for response will consist of separate analyses for the zero and for
the span data.
9.2.8 Accuracy
The percent relative accuracy (RA) of the analyzers with respect to the reference method will
be assessed by:
PI- Ci 4s-
RA = x 100%
X
where d refers to the average difference between the reference and tested methods, and
x corresponds to the average reference method value. Sd denotes the sample standard deviation
of the differences, and will be estimated based on n = 9 samples, while flv, is the t value for the
100(1 - a)th percentile of the distribution with n-1 degrees of freedom. The relative accuracy
will be determined for an a value of 0.025 (i.e., 97.5 percent confidence level, one-tailed). The
RA calculated in this way can be interpreted as an upper confidence bound for the relative bias
of the analyzer. Relative accuracy will be calculated separately for each unit of each portable
analyzer being tested.
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9.2.9 Zero/Span Drift
Statistical procedures for assessing zero and span drift will be similar to those used to assess
interrupted sampling. Zero (span) drift will be calculated as the arithmetic difference between
zero (span) values obtained before and after sampling of source emissions. No estimate can be
made of the precision of the zero and span drift values.
9.2.10 Measurement Stability
The temporal stability of analyzer response in extended sampling from a combustion source
will be assessed by means of a trend analysis on the 60 minutes of data from this test. The
existence of a trend in the data will be assessed by fitting a linear regression line, with the
difference between analyzer and corresponding reference readings as the dependent variable and
time as the independent variable. Subtracting the reference readings from the analyzer readings
in this way corrects for any variation in the source output. The null hypothesis that the slope of
the trend line is zero, i.e.,
Hq : slope = 0
H,: slope * 0
will be tested using a one-sample two-tailed t-test with n-2 = 58 degrees of freedom.
9.2.11 Inter-Unit Repeatability
The purpose of this comparison is to determine if any significant differences in performance
exist between two nominally identical commercial analyzer units operating side-by-side. Inter-
unit repeatability will be assessed for the linearity, detection limit, accuracy, and measurement
stability tests. A Student's t-test will be used as the means of comparison where appropriate.
For example, the slopes of the calibration lines determined in the linearity test, and the detection
limits determined from those test data, will be compared. For the measurement stability test,
inter-unit repeatability will be assessed by a linear regression of the inter-unit difference against
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time. The null hypothesis that the slope of the line is zero will be tested using a matched-pairs t-
test with n-2 = 58 degrees of freedom.
9.2.12 Data Completeness
Data completeness will be calculated as the percentage of possible data recovered from an
analyzer in a test. It is calculated as the ratio of the actual to the possible number of data points,
converted to a percentage, i.e.,
Data Completeness = (Na)/(NP) x 100%,
where Na is the number of actual and Np the number of possible data points.
9.3 Data Review
Records generated by test facility staff in the verification test will receive a one-over-one
review within two weeks after generation, before these records are used to calculate, evaluate, or
report verification results. These records may include laboratory record books; operating data
from the combustion sources; equipment calibration records; and data sheets used to record the
analyzers' response or other parameters in the laboratory or combustion source experiments.
This review will be performed by a test facility technical staff member involved in the
verification test, but not the staff member that originally generated the record. The review will
be documented by the person performing the review by adding his/her initials and date to a hard
copy of the record being reviewed. This hard copy will then be returned to the test facility staff
member who generated or who will be storing the record. In addition, data calculations
performed by the test facility will be spot-checked by the facility technical staff to ensure that
calculations are performed correctly. Calculations to be checked include determination of
analyzer precision, accuracy, detection limit, and other statistical calculations identified in
Section 9.2 of this test/QA plan.
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All data recorded electronically or manually, whether by the vendor or by test facility staff,
become part of the test record for reporting purposes. Manual data entries must be made in ink,
and appropriate record book pages or data sheets must be dated and signed by the responsible
staff member(s). Any error corrections to written data must be made by drawing a single line
through the error, initialing and dating the correction, and adding a short explanation for any
non-obvious error corrections. Any deviations from this test/QA plan will be documented by
recording the nature and cause of the deviation, the corrective action taken, and the impact of the
deviation on the verification test results.
9.4 Reporting
The statistical data comparisons that result from each of the tests described above will be
conducted separately for each unit of each commercial portable analyzer, and information on the
additional cost factors will be compiled. The test facility (if testing not conducted by Battelle)
will prepare a test data report for each technology that summarizes all test procedures and data,
and includes a summary of any amendments or deviations from this plan required in testing. A
package containing copies of all raw test data and records will also be prepared. The test facility
will provide the test data report to Battelle in an electronic file and hard copy, and the data
package in hard copy. Battelle will then prepare separate ETV verification reports which will
each address the analyzer provided by one commercial vendor. The results for the two units
tested will be included separately in the ETV verification report (i.e., no averaging of the two
results will be done). For each test conducted in this verification, the verification report will
present the test data, as well as the results of the statistical evaluation of those data. The ETV
verification report will briefly describe the ETV program and the AMS pilot, and will describe
the procedures used in verification testing. These sections will be common to each verification
report resulting from this verification test. The results of the verification test will then be stated
quantitatively, without comparison to any other analyzer tested, or any comment on the
acceptability of the analyzer's performance. The preparation of draft ETV verification reports,
the review of reports by vendors and others, the revision of the reports, final approval, and the
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distribution of the reports, will be conducted as stated in the Generic Verification Protocol for
the Advanced Monitoring Systems Pilot.(8) Preparation, approval, and use of Verification
Statements summarizing the results of this test will also be subject to the requirements of that
same Protocol.
10.0 HEALTH AND SAFETY
Battelle staff, and subcontracted testing laboratory staff involved in this verification test, will
operate under established health and safety requirements and guidance. Vendor staff will be
operating their analyzers in the test facility during the verification test. Health and safety
requirements and guidance are provided in the following paragraphs.
10.1 Access
Vendor staff will be required to sign in at the test facility at the beginning of each day and
sign out at the end of each day for the period of the verification test. Access will be limited to
regular workdays between 7 a.m. and 6 p.m., and is restricted to buildings and areas where the
verification test is being conducted.
10.2 Potential Hazards
Vendor staff will only be operating their portable analyzers during the verification test. They
are not responsible for, nor permitted to, generate dilution gases, operate combustion sources, or
perform any other verification activities identified in this test/QA plan. Operation of portable
emission analyzers does not pose any known chemical, fire, mechanical, electrical, noise, or
other potential hazard. Operation of emissions sources may pose fire and/or noise hazards.
Vendor staff will be provided with safety training, shown the location of fire extinguishers and
gas shutoff valves, and will be provided with hearing protection when necessary.
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10.3 Training
All Battelle, EPA, and vendor staff will be given a safety briefing prior to their activities in
the test facility. This briefing will include a description of emergency operating procedures (i.e.,
in case of fire, earthquake, bomb, laboratory accident) and identification, location, and operation
of safety equipment (e.g., fire alarms, fire extinguishers, eye washes, exits).
10.4 Safe Work Practices
The following safe work practices must be followed by all staff in this verification test:
Staff will be required to wear long pants and enclosed shoes (no open-toed sandals).
Laboratory coats and protective glasses will be provided where necessary.
Eating, drinking, and smoking are only permitted in designated areas.
A "three warning" system will be used to enforce compliance with these safety practices:
First infraction - violator receives a verbal warning
Second infraction - violator receives a written warning
Third infraction - violators will be requested to leave the test facility.
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Test/Quality Assurance Plan
Verification of Portable Gaseous Emission Analyzers
Page 56 of 56
January 3, 2002
11.0 REFERENCES
1. Quality Management Plan (QMP) for the ETV Advanced Monitoring Systems Center,
Version 3.0, U.S. EPA Environmental Technology Verification Program, prepared by
Battelle, Columbus, Ohio, December, 2001.
2. Environmental Technology Verification Program Quality and Management Plan for the Pilot
Period (1995-2000), EPA-600/R-98/064, U.S. Environmental Protection Agency, Cincinnati,
Ohio, May 1998.
3. Portable NOx Analyzer Evaluation for Alternative Nitrogen Oxides Emission Rate
Determination at Process Units, California South Coast Air Quality Management District,
September 21, 1994.
4. Determination of Nitric Oxide, Nitrogen Dioxide and NOx Emissions from Stationary
Combustion Sources by Electrochemical Analyzer, CTM-022.WPF, Emission Measurement
Center, Technical Support Division, OAQPS, U.S. EPA, May 1995.
5. Determination of Nitrogen Oxides, Carbon Monoxide, and Oxygen Emissions from Natural
Gas-Fired Engines, Boilers and Process Heaters Using Portable Analyzers, Gas Research
Institute Method GRI-96/0008; Emission Measurement Center Conditional Test Method
CTM-030, Revision 7, U.S. EPA, October 13, 1997.
6. Emission Measurement Center Approved Alternative Method: Acceptable Alternative
Procedure to Section 5.6.1 of Method 20 in Appendix A of 40 CFR Part 60 (Also Required
by Method 7E in Appendix A), to Performance Check the Efficiency of the Nitrogen Dioxide
(N02) to Nitric Oxide (NO) Converter; EMC ALT-013, Emission Measurement Center, U.S
EPA, September 1994.
7. Traceability Protocol for Establishing True Concentrations of Gases Used for Calibrations
and Audits of Continuous Source Emission Monitors: Protocol Number 1, U.S.
Environmental Protection Agency, Quality Assurance Division, Research Triangle Park,
North Carolina, June 1978.
8. Generic Verification Protocol for the Advanced Monitoring Systems Center, Battelle,
Columbus, Ohio, November 1998.
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