United States Office of Air Quality EPA-340/1-86-01 6
Environmental Protection Planning and Standards July 1986
Agency Washington, DC 20460
Air
v>EPA A Guideline for
Surface Coating
Calculations
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EPA-340/1-86-016
A Guide For Surface Coating Calculations
Prepared by
PEI Associates, Inc.
11499 Chester Road
Post Off ice Box 46100
Cincinnati, Ohio 45246-0100
Contract No. 68-02-3963
Work Assignment No. 6
Prepared for
Project Officer: John Busik
Work Assignment Manager: Dwight Hlustick
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air Quality Planning and Standards
Stationary Source Compliance Division
Washington, DC 20460
July 1986
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DISCLAIMER
This report was prepared for the U.S. Environmental Protection Agency by
PEI Associates, Inc., Cincinnati, Ohio, under Contract No. 68-02-3767, Work
Assignment No. 67. The contents of this report are reproduced herein as re-
ceived from the Contractor. The opinions, findings, and conclusions expressed
are those of the author and not necessarily those of the U.S. Environmental
Protection Agency.
n
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CONTENTS
Figures iv
Tables iv
Acknowledgment v
Abstract vi
1. Introduction 1
1.1 Background 1
1.2 Description of VOC calculations 2
1.3 Negligibly photochemically reactive materials 3
2. Basic Calculations 5
2.1 Determining the mass of VOC emitted per volume of solids 5
2.2 Determining the mass of VOC emitted per volume of coating 6
less water
3. Transfer Efficiency 9
3.1 Determining the mass of VOC emitted per volume of solids 9
applied
3.2 Calculating average transfer efficiency 10
4. Compliance Determinations 12
4.1 Calculating coating compliance with a standard 12
4.2 Calculating compliance when add-on controls are used 13
5. Equivalency Determinations 16
5.1 Calculating allowable hourly emissions for a solvent-borne 16
coating
5.2 Equivalency calculations for a can coating operation 17
(continued)
ill
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CONTENTS (continued)
Page
6. Complex Calculations 23
6.1 Compliance determination for auto plant primer-surfacer 23
(guide coat) operation
6.2 Determining compliance for a large appliance coating line 26
using several types of spray equipment
7. Graphs and Tables Useful in Approximating and Double-Checking 30
Surface Coating Calculations
References 41
Appendices
A Glossary of Air Pollution Control of Industrial Coating A-l
Operations. EPA-450/3-83-013R. December 1983. pp. 26-29.
B Procedures for Certifying Quantity of Volatile Organic B-l
Compounds Emitted by Paint, Ink, and Other Coatings.
%
EPA-450/3-84-019. December 1984.
Reference Method 24. C-l
iv
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FIGURES
Number Page
1 Graph For Determining Equivalent Solids/VOC (Solvent) 31
Contents of Waterborne and Organic-Borne Coatings
2 Graph For Determining Pounds of VOC (Solvent) Per Gallon 32
Of Coating Solids
3 Smaller-Scale Graph For Determining Pounds of VOC (Solvent) 33
Per Gallon of Coating Solids
TABLES
Number Page
1 Example Calculation of Average TE When Several Different 11
Coating Application Methods Are Used
2 Suggested Format For Determining Compliance for Can Coating 21
Operations
3 Large Appliance Multitransfer Efficiency Calculation 27
4 CTG Volume Percent Solids Equivalency Data 34
5 CTG Equivalency Data 36
6 Equivalent Solids Deposited Limits 39
7 Metric Conversion Factors 40
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ACKNOWLEDGMENT
This guideline was prepared for the U.S. Environmental Protection Agency
by PEI Associates, Inc. under Contract No. 68-02-3963. It is primarily a re-
vision of a preliminary draft manual with the same title, dated January 1982,
and prepared by Messrs. William Polglase, Brock Nicholson, and Tom Williams of
the Control Programs Development Division (CPDD), U. S. Environmental Protec-
tion Agency, Research Triangle Park, North Carolina. PEI especially appreci-
ates the support and input given by Mr. Dwight Hlustick, the Work Assignment
Manager, during the preparation of this guideline. The review and comments
provided by Messrs. Robert Blaszczak, Douglas Cook, Richard Dalton, Paul
Kahn, Laxmi Kesari, William Polglase, Michael Pucci, David Salman, Dennis San-
tella, and James Topsale are also gratefully acknowledged.
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ABSTRACT
The calculation of volatile organic compound emissions from surface coat-
ing operations to determine compliance is often a complicated task, sometimes
creating confusion with compliance authorities and sources alike. In an at-
tempt to minimize this confusion, EPA (OAQPS) has periodically issued guidance
in this area, generally in the form of memoranda to the EPA Regional Offices.
EPA guidance for submitting data on surface coatings and performing basic cal-
culations is contained in the document entitled "Procedures for Certifying
Quantity of Volatile Organic Compounds Emitted by Paint, Ink and Other Coat-
ings," EPA 450/3-84-019, published in December 1984.
"A Guideline for Surface Coating Calculations" takes the above guidance
process one step further. Example calculations are included for basic emis-
sion problems, compliance determinations, equivalency determinations, appli-
cation of transfer efficiency, and calculations involving complex multiproduct
plants. Graphs anci tables useful in approximating and double-checking these
calculations are also included.
•V3-X
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SECTION 1
INTRODUCTION
1.1 BACKGROUND
Surface coating entails the deposition of a solid film on a surface
through the application of a coating material such as paint, lacquer, or var-
nish. Surface coating operations are significant volatile organic compound
(VOC) emission sources. Most coatings contain VOCs which evaporate during the
coating application and curing processes, rather than becoming part of the dry
film.
The U.S. Environmental Protection Agency (EPA) has issued Control Tech-
niques Guidelines (CTGs) for many surface coating operations, including cans,
metal coils, paper, fabric, automobiles, light-duty trucks, metal furniture,
large appliances, magnet wire, miscellaneous metal parts and products, graphic
arts, and flatwood paneling. The emission limits recommended in these guide-
lines have been adopted by many state and local agencies. The EPA has also
issued new source performance standards (NSPS) for many surface coating opera-
tions, including automobile, light-duty trucks, beverage cans, metal coils,
large appliances, metal furniture, pressure sensitive tapes and labels, vinyl
printing and topcoating, and publication rotogravure printing.
To comply with these regulations, a surface coating operator might elect
to change to low VOC content coatings, to use add-on controls such as inciner-
ation or carbon adsorption, or to improve transfer efficiency. In cases where
compliance is achieved by a change in coating alone, VOC emissions can be cal-
culated from the VOC content of the coating as applied to the substrate. When
add-on controls or transfer efficiency improvements are used, more complex
calculations can be performed to determine the effectiveness of the control
strategy. It is more convenient (and frequently more reliable) to establish
VOC compliance or non-compliarice through these calculations than it is to
measure total VOC emissions directly.
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The emission limits for existing sources recommended in the CTGs and
adopted by many state and local agencies are expressed in terms of pounds of
VOC per gallon of coating less water. These units are directly useful only
for cases where compliance is achieved with low VOC content coatings alone.
When add-on controls or transfer efficiency improvements are used, compliance
calculations must be done on an equivalent solids basis. The reasons for this
are explained graphically in Glossary of Air Pollution Control of Industrial
Coating Operations, EPA-450/3-83-013R, December 1983. Pages 26-29 of this
document are located in Appendix A. The emission limits in most surface coat-
ing NSPSs are expressed in terms of pounds of VOC per gallon of coating solids
applied. The reader should review this concept in Appendix A before contin-
uing in this guideline manual. This calculation guide assumes that the solids
used or applied in a specific process remain constant for a given example
(solids equivalency).
1.2 DESCRIPTION OF VOC CALCULATIONS
This document presents sample calculations typical of those used to
determine compliance or to evaluate control strategies. These step-by-step
calculations are accompanied by explanations that are useful to persons
unfamiliar with surface coating operations. Basic calculations are included
along with calculations to determine compliance and equivalency (necessary for
evaluating bubbles, offsets, netting, etc.). Transfer efficiency problems
requiring a series of calculations are included.
The basis for most of the sample calculations is the information and
procedures discussed in Procedure for Certifying Quantity of Volatile Organic
Compounds Emitted by Paint, Ink, and Other Coatings. EPA-450/3-84-019, Decem-
ber 1984, which is reprinted as Appendix B of this report and referred to as
the "VOC Data Sheets". The first VOC Data Sheet provides information on the
VOCs present in a coating when it is sold by the manufacturer to the coater.
This is referred to as the VOC content of the coating "as supplied by the
coating manufacturer to the user." The second VOC Data Sheet provides infor-
mation on the VOCs present in the coating as it is used by the coater and in-
cludes the effect of dilution solvent added before application. This is re-
ferred to as the VOC content "as applied to the substrate by the user." For
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dip or flow coating operations, this should include any make-up solvent which
is added to a coating to replace evaporated solvent and therefore maintain a
specific viscosity of the coating being applied. The calculations in this
document assume that the inspector has obtained the coating data from the VOC
Data Sheets. However, it is up to the inspector to verify this data. EPA
Reference Method 24 or individual ASTM methods are the final judge in deter-
mining compliance. Appendix C contains a copy of Reference Method 24.
Some confusion may exist regarding the meanings and proper uses of terms.
As defined in Appendix B, the term "as applied" means the condition of a coat-
ing after dilution by the user just prior to application to the substrate.
However, the term "solids applied" means the amount coating solids that
actually adheres to the object being coated, not the amount of solids leaving
the applicator. In contrast, the term "solids used" refers to the total
amount of solids used in an application, not the amount of solids that act-
ually adheres to substrate. Care should be taken when using these terms to
avoid confusion.
1.3 NEGLIGIBLY PHOTOCHEMICALLY REACTIVE MATERIALS
A volatile organic compound is defined in 40 CFR Subpart A, General Pro-
visions, §60.2, as any organic compound which participates in atmospheric pho-
tochemical reactions; or which is measured by a reference method, an equiva-
lent method, or an alternative method; or which is determined by procedures
specified under any subpart. The EPA considers the following organic solvents
to have negligible photochemical reactivity, and therefore does not consider
them to be VOCs:
Methane1
Ethane1
1,1,1-trichloroethane (methyl chloroform)1
Methylene chloride2
Trichlorofluoromethane (CFC-11)3
Dichlorodifluoromethane (CFC-12)3
Chlorodifluoromethane (CFC-22)3
Trifluoromethane (CFC-23)3
Trichlorotrifluoroethane (CFC-113)1
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Dichlorotetrafluoroethane (CFC-114)3
Chloropentafluoroethane (CFC-115)3
Many states also do not consider some or all of these materials to be VOCs.
Two of these compounds, 1,1,1-trichloroethane and methylene chloride, are
used as solvents in some coatings. These materials should not be counted as
VOCs if they are "exempt" from the applicable regulation. The method for
discounting these materials is described in some of the examples and in
Appendix B. Generally, these materials, when "exempt" from the applicable
regulation, are treated in the same manner as water in emission calculations.
Only the compounds listed above and any compounds given the status of
"negligibly photochemically reactive" by the U.S. EPA in a future Federal Re-
gister may be considered as exempt from Federal enforcement of applicable
State SIP VOC regulations. Also, Rule 66 should not be referenced for exempt-
ing compounds as per 42 FR 35314, July 8, 1977.
2 FR 3D314, July 8, 1977
245 FR 32042, June 4, 1979
345 FR 48941, July 22, 1980
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SECTION 2
BASIC CALCULATIONS
This section presents examples of basic types of calculations. The
examples closely follow the VOC Data Sheets (Appendix B).
2.1 DETERMINING THE MASS OF VOC EMITTED PER VOLUME OF SOLIDS
Example 1 -
Determine the mass of VOC emitted per volume of solids for a solvent-borne
coating. The following data are given:
A. Coating Density =10.0 Ib/gal
B. Total Volatiles = 60 percent by weight
C. Water Content = 0
D. Organic* Volatiles
Content = 60 percent by weight
E. Nonvolatiles Content
(Solids) = 35 percent by volume
Mass of VOC emitted per volume of solids is:
10.0 Ib coating 0.60 Ib VOC 1 gal coating = 17.1 Ib VOC
gal coating Ib coating 0.35 gal solids gal solids
Example 2 -
Determine the mass of VOC emitted per volume of solids for a waterborne
coating. The following data are given:
A. Coating Density = 9.0 Ib/gal
B. Total Volatiles = 70 percent by weight
C. Water Content = 30 percent by weight
D. Organic* Volatiles
Content = 70-30=40 percent by weight
E. Nonvolatiles Content = 19.6 percent by volume
(Solids)
*Photochemically reactive materials only.
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Mass of VOC emitted per volume of solids is:
9.0 1b coating 0.40 1b VOC 1 gal coating _ 18.4 Ib VOC
gal coating Ib coating 0.196 gal solids gal solids
Example 3 -
Determine the mass of VOC emitted per volume of solids for a coating that
contains some negligibly photochemically reactive (NPR) solvents.
The following data are given:
A. Coating Density = 11.0 Ib/gal
B. Total Volatiles = 80 percent by weight
C. NPR Solvent Content = 40 percent by weight
D. Organic* Volatiles
Content = 40 percent by weight
E. Nonvolatiles Content = 15 percent by volume
(Solids)
Mass of VOC emitted per volume of solids is:
11.0 Ib coating 0.40 Ib VOC 1 gal coating = 29.3 Ib VQC
gal coating x Ib coating 0.15 gal solids gal solids
2.2 DETERMINING THE MASS OF VOC EMITTED PER VOLUME OF COATING LESS WATER
Example 4 -
Determine the mass of VOC emitted per volume of coating less water for a
solvent-borne coating. The following data are given:
A. Coating Density = 10 Ib/gal
B. Total Volatiles = 60 percent weight
C. Water Content = 0
D. Organic* Volatiles
Content = 60 percent weight
Mass of VOC per volume of coating less water is:
10 Ib coating 0.60 Ib VOC 1 gal coating
gal coating Ib coating (1-0) gal coating less water
6 Ib VOC
gal coating less water
*Photochemically reactive materials only.
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Example 5 -
Determine the mass of VOC emitted per volume of coating less water for a
water-borne coating. The following data are given:
A. Coating Density =9.0 Ib/gal
B. Total Volatiles = 70 percent by weight
C. Water Content = 30 percent by weight
D. Organic* Volatiles
Content = 70-30=40 percent by weight
The mass of water in the coating is:
9.0 Ib coating 0.3 1b water _ 2.7 1b water
gal coating Ib coating " gal coating
The volume of water in the coating is:
2.7 Ib water 1 _ 0.32 gal water
gal coating 8.33 Ib water ~ gal coating
gal water
The mass of VOC in the coating is:
9.0 Ib coating 0.4 Ib VOC = 3.6 Ib VOC
gal coating Ib coating " gal coating
The mass of VOC emitted per volume of coating less water is:
3.6 Ib VOC
gal coating" _ 5.3 Ib VOC
1 gal coating - 0.32 gal water ~ gal coating less water
gal coating
Example 6 -
Determine the mass of VOC emitted per gallon of coating less negligibly photo-
chemically reactive material for a coating that contains some negligibly
photochemically reactive material.
The following data are given:
A. Coating Density = 10.5 Ib/gallon
B. Total Volatiles = 80 percent by weight
C. NPR Solvent Content = 40 percent by weight
D. Organic* Volatiles
Content = 40 percent by weight
E. NPR Solvent Density = 11.0 Ib/gal
*Photochemically reactive materials only.
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The mass of VOC per volume of coating is:
10.5 1b coating 0.4 1b VOC _ 4.2 1b VOC
gal coating Ib coating ~ gal coating
The mass of NPR solvent in the coating is:
10.5 Ib coating 0.4 Ib NPR solvent = 4.2 Ib NPR solvent
gal coating Ib coating ~ gal coating
The volume of NPR solvent in the coating is:
4.2 Ib NPR solvent 1 = 0.38 gal NPR solvent
gal coating x 11.0 Ib NPR solvent gal coating
gal NPR solvent
The mass of VOC per gallon of coating less NPR solvent is:
4.2 Ib VOC
gal coating _ 6.8 Ib VOC
1 gal coating - 0.38 gal NPR solvent ~ gal coating less NPR solvent
1 gal coating
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SECTION 3
TRANSFER EFFICIENCY
When spray guns are used to apply coatings, much of the coating material
either bounces off the surface being coated or misses it altogether. Transfer
efficiency (TE) is the ratio of the amount of coating solids deposited on the
coated part to the amount of coating solids used. Regardless of the TE, all
of the VOCs in the dispensed coating are emitted whether or not the coating
actually reaches and adheres to the surface. Consequently, improved TE can
reduce VOC emissions because less coating is used. EPA has defined baseline
transfer efficiencies of 60 percent for RACT in metal furniture and appliance
coating and 30 percent for RACT waterborne equivalence in the automobile in-
dustry (for both primer-surfacer and topcoat applications). If a base TE has
not been documented by EPA, then the company must satisfactorily document
their base TE prior to equivalency calculations/demonstrations. To obtain TE
credits, a company must prove its baseline TE with documentation, and document
the new TE.
3.1 DETERMINING THE MASS OF VOC EMITTED PER VOLUME OF SOLIDS APPLIED
Example 1 -
Determine the mass of VOC emitted per volume of solids applied given the fol-
lowing data:
A. VOC content of coating = 4.0 Ib VOC
gal solids
B. Transfer efficiency = 40 percent
Mass of VOC emitted per volume of solids applied is:
4.0 Ib VQC 1 gal solids used = 10.0 Ib VOC
gal solids 0.4 gal solids applied ~ gal solids applied
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Example 2 -
Determine the mass of VOC emitted per volume of solids applied given the fol-
lowing data:
A. VOC content of coating = 3.0 Ib VOC/gal coating less water
B. Nonvolatiles content = 55 percent by volume
C. Transfer efficiency = 60 percent
D. Water Content = None
3.0 Ib VOC 1 gal coating less water 1 gal solids used
gal coating less water 0.55 gal solids 0.60 gal solids applied
= 9.1 Ib VOC
1 gallon solids applied
Note: For a waterborne coating, be careful of using pounds of VOC per gallon
of coating less water and volume nonvolatiles content as a fraction of
the total coating including water. These two items cannot simply be
combined to get pounds of VOC per gallon of solids. The best method
is to follow Example 2 in Section 2 and then factor in transfer effi-
ciency. Alternatively, the volume nonvolatiles content could be de-
termined for the coating less water if the volume fraction water is
known or calculated as follows:
='••"".
3.2 CALCULATING AVERAGE TRANSFER EFFICIENCY
Example 3 -
A plant operates two coating lines. Each line uses both manual electrostatic
spray guns (TE = 60 percent) and rotating-head electrostatic spray guns (TE =
80 percent). Table 1 contains the applicable data. What is the average
transfer efficiency?
Awpranp TF - total liters of solids deposited _ 38.4 + 36.8 n
average it - t()tal mers Qf solids use(J 64 + 46 x 10°
75.2
110
x 100 = 68 percent
10
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TABLE 1. EXAMPLE CALCULATION OF AVERAGE TE WHEN
SEVERAL DIFFERENT COATING APPLICATION METHODS ARE USED
Coating line
A
B
TOTAL
Total
1 i ters
of
coating
used
100
100
Volume
percent
solids
50
60
Total
liters
of
solids
used
50
60
Application Method
Manual electrostatic spray
(TE = 60%)*
Liters
of
coating
used
80
40
Liters
of
solids
used
40
24
64
Liters
of
' solids
deposited
24
14.4
38.4
Rotating-head electro-
static spray (TE = 80%)*
Liters
of
coating
used
20
60
Liters
of
solids
used
10
36
46
Liters
of
solids
deposited
8
28.8
36.8
*These TE values are illustrative values only. Actual TE must be determined to calculate actual emissions,
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SECTION 4
COMPLIANCE DETERMINATIONS
4.1 CALCULATING COATING COMPLIANCE WITH A STANDARD
Example 1 -
A coater is required to meet an emission limit of 3.5 pounds of VOC per gallon
of coating less water. Does a coating with a density of 12 pounds per gallon
that contains 25 weight percent VOC comply? The coating contains no water or
negligibly photochemically reactive solvents.
12 Ib coating 0.25 Ib VOC 1 gal coating
gal coating Ib coating (1-0) gal coating less water
3 Ib VOC
gal coating less water
So, the coating complies with the regulation.
Example 2 -
A coater is required to meet an emission limit of 4.0 pounds VOC per gallon of
solids. Does a coating with a density of 10 pounds per gallon that contains
60 weight percent volatiles, 45 weight percent water, and 30 volume percent
solids comply?
The weight percent organic volatiles is 60-45=15.
:
The VOC content of the coating is:
10 Ib coating 0.15 Ib VOC 1 gal coating = 5 Ib VOC
gal coating Ib coating 0.30 gal solids gal solids
So, the coating does not comply with the regulation.
12
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Example 3 -
A coater is required to meet an emission limit of 10 pounds VOC per gallon of
solids applied. Does the coating in Example 2 comply if it is applied at a
transfer efficiency of 80 percent?
5 Ib VOC 1 gal solids used _ 6.3 Ib VOC
gal solids x 0.80 gallon solids applied ~ gal solids applied
So, the coating meets the regulation.
Example 4 -
A metal furniture coater uses a coating containing 0.40 kg VOC/liter of coat-
ing (less water and exempt solvents). The coating contains 55 volume percent
solids. The transfer efficiency is 87 percent. Is the plant in compliance if
the maximum allowable emissions are 1.0 kg VOC/liter solids applied?
The solution is found by using the following basic equation:
mass of VOC used 1 _ mass of VOC used
/\
volume of coating solids used TE volume of coating solids applied
Emissions are:
1 liter of coating less water
0.40 kg VOC and exempt solvents
1 liter of coating less water 0.55 liter solids
and exempt solvents
1 liter solids 0.84 kg VOC
^
In
0.87 liter solids 1 liter solids applied
applied
Since 0.84 is less than 1.0, the coating operation is in compliance.
Note: This example is similar to Example 2 in Section 3.1. Therefore, the
note mentioned after Example 2 applies to this example too.
4.2 CALCULATING COMPLIANCE MEN ADD-ON CONTROLS ARE USED
Example 5 -
A coater is required to meet an emission limit of 6 pounds of VOC per gallon
of solids. What percent emission reduction is needed if the coater uses a
coating with 22 pounds of VOC per gallon of solids?
13
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22 fi 1 fi
x 100 = x 100 = 73 percent emission reduction
Example 6 -
A coater is required to meet an emission limit of 3.7 pounds of VOC per gallon
of coating less water. What percent emission reduction is needed if the coat-
er uses a solvent-borne coating with 5.0 pounds of VOC per gallon of coating
less water and a volume solids content of 25 percent?
This calculation must be done on a solids basis. First, the emission limit
must be converted to pounds of VOC per gallon of solids. To do this, an as-
sumed VOC density of 7.36 pounds per gallon is used to calculate the volume
solids content of the "presumptive" RACT coating.
3.7 Ib VOC
x 713ja]bV$jc * 100 = 50 volume percent VOC
gal coating less water
100-50 = 50 volume percent solids
3.7 Ib VOC 1 gal coating = 7.4 Ib VOC
gal coating 0.50 gal solids ~ gal solids
Next, the VOC content of the coating used must also be calculated on a solids
basis.
5.0 Ib VOC 1 gal coating _ 20 Ib VOC
A
gal coating 0.25 gal solids gal solids
Now the required percent reduction can be calculated.
20-7.4
20
Ndtes:
x 100 = 63 percent emission reduction
1. An erroneous result is obtained if this calculation is not done on a solids
basis. Using pounds of VOC per gallon of coating less water the result would
be:
c"n * 100 = 26 percent emission reduction
0 • U
This would not give equivalent emissions as it does not take into account that
the "presumptive" RACT coating not only has lower VOC content, but higher
solids content as well.
14
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2. An assumed VOC density of 7.36 pounds per gallon is used to calculate the
volume solids content of the "presumptive" RACT coating because this same
value was used to determine the "presumptive" recommended RACT emission limits
from volume solids data.
3. The volume solids content of actual coatings should be determined directly
from coating formulation data as described in the VOC Data Sheets. Ocassion-
ally, it may be useful to back calculate volume solids from VOC content and
actual solvent or VOC density, but this must be done with extreme caution.
When an inspector gathers data on the actual coatings used at a facility, the
volume solids content should be obtained from coating formulation data from
the facility or the coating manufacturer. The volume solids content should
not be back calculated.
15
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SECTION 5
EQUIVALENCY DETERMINATIONS
Equivalency calculations are required when compliance decisions must be
made for replacement coatings, bubbles, offsets, netting, etc. This type of
calculation relates primarily to the CTG source categories. This section pre-
sents example equivalency calculations.
VOC equivalency calculations must be made on a solids basis. The amount
of solids needed to coat a surface to a particular film thickness is the same
regardless of the coating composition used. Reducing the solids content of an
organic solvent-borne coating increases the quantity of coating required and
increases VOC emissions because more coating is used and the coating has a
higher VOC content.
5.1 CALCULATING ALLOWABLE HOURLY EMISSIONS FOR A SOLVENT-BORNE COATING*
Example 1 -
A surface coater uses 10 gallons per hour of a coating that contains 5.5 Ib
VOC per gallon of coating and 25 volume percent solids. New regulations
indicate that the coating formulation must meet an emission limit of 3.0 Ib of
VOC per gallon of coating (with a solvent density of 7.36 Ib per gallon) or
the coater must control VOC emissions to an equivalent level. Assuming that
the production rate (solids usage rate), transfer efficiency, and film
thickness stay constant, what are the coater's "allowable" hourly VOC
emissions?
For the existing coating, the actual VOC emissions are:
10 gal coating 5.5 Ib VOC _ 55 Ib VOC
h x gal coating ~ h
*This example presents a method for determining hourly VOC mass emissions for
offset calculations; however, RACT limitations should normally be based on
either applicable coating formulations or control efficiency requirements. An
hourly cap would normally only be used in addition to these RACT limitations.
16
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The solids usage rate is:
10 gal coating 0.25 gal solids _ 2.5 gal solids
h gal coating h
For the complying coating, the VOC (solvent) volume fraction is:
3.0 1b VOC 1 gal VOC _ 0.41 gal VOC
gal coating x 7.36 Ib VOC ~ gal coating
The complying coating solids volume fraction is:
in n di - 0.59 gal solids
l.u - u.4i - coating
Using the solids usage rate calculated above, the gallons of complying coating
required are:
2.5 gal solids gal coating _ 4.24 gal complying coating
h x 0.59 gal solids h
The emissions rate at the existing solids applied rate is:
3.0 Ib VOC 4.24 gal coating _ 12.72 Ib VQC
gal coating h ~ h
5.2 EQUIVALENCY CALCULATIONS FOR A CAN COATING OPERATION
Example 2 -
The RACT equivalence requirements for can coating operations are tabulated in
45 FR 80825, dated December 8, 1980. An analysis of two coatings used in an
actual plant is:
Coating Coating
No. 1 No. 2
(1) Actual pounds of VOC per gallon of coating less 5.42 1.09
water and exempt solvents as applied
(2) Gallons of each coating applied 110 240
(3) Control efficiency, percent 0.81
(4) Volume percent water and exempt solvents
in coatings -- 41.3
(continued)
17
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Coating Coating
No. 1 No. 2
(5) Volume percent solids 26.4 50.0
(6) Allowable emission limit, Ib VOC/gal coating 2.8 2.8
less water and exempt solvents
Calculate the following:
(1) Gallons of solids applied.
(2) Pounds of VOC per gallon of solids.
(3) Pounds of VOC emitted.
(4) Allowable VOC emissions.
Answers:
(1) The gallons of solids applied can be calculated as follows:
Gallons of solids applied = (gallons of coating used) x (volume
percent solids) * 100%
(Since the quantity of solids used in the equation appears as a
percentage it is necessary to divide by 100%.)
Coating No. 1:
110 „, coating applied x '* 29
Coating No. 2:
9/in „=,! ,.„*+•!,„, anni-5Q,4 v 50 gal solids 120 gal solids
240 gal coating applied x 100 jja1 coating - *pplied
(2) As noted on Page 10, the pounds of VOC per gallon of solids can be
calculated as follows:
Ib VOC _ Ib VOC/gal coating less water
gal of solids " volume percent solids
100-volume percent water
18
-------
Coating No. 1:
5.42 1b VOC 100 gal coating 100 - 0 gal coating less water
gal coating 26.4 gal solids 100 gal coating
less water
_ 20.53 Ib VOC
gal solids
Coating No. 2:
1.09 Ib VOC 100 gal coating 100 - 41.3 gal coating less water
gal coating 50.0 gal solids 100 gal coating
less water
= 1.28 Ib VOC
gal solids
(3) The pounds of VOC emitted can be calculated as follows:
gal of solids x ga1 of solids x ^ " overa11 control efficiency*)
Coating No. 1:
x 29'° gal solids x (1 ~ °'81) = U3A lb voc
Coating No. 2:
gal Sol1ds x (1 ~ 0) = 153'6 1b VOC
(4) The allowable VOC emissions can be calculated as follows:
As calculated in Item (2), the gallons of solids applied for coatings No,
1 and No. 2 were 29 and 120, respectively. Assume that the coater will
apply the same volume of solids with a RACT complying coating.
Given: (1) Emission limit: 2.8 lb VOC/gal coating
(2) VOC density: 7.36 lb VOC/gal
*The overall control efficiency is equal to the fraction of total VOC used
that is destroyed or recovered by the control system. Overall control effi-
ciency = capture device efficiency x control device efficiency.
19
-------
Allowable pounds of VOC = gallons of complying coating applied x allow-
able emission limit,
= gal solids applied (per unit of time) 2.8 Ib VOC
volume fraction solids in complying coating gal coating less water
and exempt solvents
Volume fraction VOC:
2.8 Ib VOC 1 gal VOC _ 0.38 gal VOC
gal coating 7.36 Ib VOC gal coating
Volume fraction solids:
' - °-38 9.1 -tfng -
Allowable pounds of VOC for Coating No. 1:
29 aal solids x 1 ^ coating 2.8 Ib VOC '
& gal solids x Q 62 gal Sol1ds x gfll coating
= 131 Ib VOC
Allowable pounds of VOC for Coating No. 2:
^n i T-J gal coating 2.8 Ib VOC
120 gal solids x 0.6j ga1 So113s * gal coating
= 542 Ib VOC
Table 2 shows the calculation sequence.
20
-------
TABLE 2. SUGGESTED FORMAT FOR DETERMINING COMPLIANCE FOR CAN COATING OPERATIONS.
Lb VOC/
gal
coating
less
water
(a)*
Volume
%
solids
(b)*
Volume
%
solvent
(c)
Volume
%
water
(d)*
Lb VOC/
gal
solids1
(e)
Application
rate (gal/
units
produced
(f)*
Units
pro-
duced
(9)*
Gal
coating
applied
(f x g)
(h)
Gal
solids'
applied
(b x h T 100)
(i)
Over-
all
Add-
on
Con-
trol
effi-
ciency2
(J)*
Lb
of VOC
[e x i]
(1 - J)
(k)
Actual Emissions3
Sheet coating
Sheet coating
Sheet coating
Side seam
Inside spray
End compound
5.42
1.09
5.06
6.34
3.91
4.20
26.4
50.0
31.2
13.9
16.0
42.9
.
-
-
-
-
-
0
41.3
0
0
65.9
0
20.52
1.28
16.23
45.59
8.33
9.80
22
10
10
1.5
8
1.5
5
24
24
18
24
24
110
240
240
27
192
36
29.0
120.0
74.9
3.8
30.7
15.4
0.81
-
0.81
-
-
-
113.0
153.0
231.0
173.8
255.7
150.0
ACTUAL TOTAL EMISSIONS
1,077.5
Allowable Emissions Using Complying Coating''
Shtet coating
Sheet coating
Sheet coating
Side seam
Inside spray
End compound
2.8
2.8
2.8
5.5
4.2
3.7
62.0
62.0
62.0
25.3
42.9
49.7
38.0
38.0
38.0
74.7
57.1
50.3
_
-
-
-
-
-
4.52
4.52
4.52
21.76
9.78
7.44
9.4
8.1
5.0
0.8
3.0
1.3
b
24
24
18
24
24
47
194
121
15
72
31
29.0
120.0
74.9
3.8
30.7
15.4
.
.
.
_
-
-
131.0
542.0
338.0
82.7
300.2
114.6
ACTUAL TOTAL EMISSIONS
1,509.5
*Note: Data in columns a, b, d, f, g, and j (under actual emissions) were obtained from plant records including thinning
solvent. Data in columns a, b, and d were determined using procedures in the VOC Data Sheets.
'For actual coatings, e
For complying coatings, e = 1 - K
-------
TABLE 2. (continued)
no
ro
D = Presumed density of VOC for complying coating (7.36 Ib/gal).
2Control efficiency varies with emission control devices used. The percent capture and control efficiency must be established by
using approved test methods. The source must always maintain process and control system parameters as close as possible to
those used in the original capture and control efficiency demonstration. If there are any significant changes in these para-
meters, the source must make a new capture and/or control efficiency demonstration as deemed appropriate by the compliance au-
thority.
3Concept based on the following principal for comparing actual and allowable emissions: Ib VOC emitted = Ib VOC/gal of solids x
gal of solids applied per unit. (Same gal of solids applied for actual and allowable emissions.)
''Complies with State VOC emission limitations.
-------
SECTION 6
COMPLEX CALCULATIONS
This section presents example calculations demonstrating situations that
may require a series of calculations.
6.1 COMPLIANCE DETERMINATION FOR AUTO PLANT PRIMER-SURFACER (GUIDE COAT)
OPERATION
Example 1 -
An auto primer-surfacer operation uses a coating that contains 3.58 Ib VOC/gal
of coating with a transfer efficiency of 50 percent. The RACT emission limit
is 2.8 Ib VOC/gal of coating less water at 30 percent transfer efficiency
(waterborne equivalence). Is the operation in compliance?
Given: (1) The manufacturer's data show that the undiluted coating has
50.0 volume percent solids.
(2) The plant adds 0.05 gal of thinner blend per gallon of un-
diluted coating:
(a) 0.02 gallon of thinner No. I/gallon undiluted coating
(thinner density 7.36 Ib/gal).
(b) 0.02 gallon of thinner No. 2/gallon undiluted coating
(thinner density 5.43 Ib/gal).
(c) 0.01 gallon of thinner No. 3/gallon undiluted coating
(thinner density 9.52 Ib/gal).
(3) The density of the undiluted coating is 10.25 Ib/gal.
(4) Weight fraction of VOC in undiluted coating =
0.333 Ib VOC solvent
Ib undiluted coating
23
-------
First, verify the VOC content of the coating. In order to do this, the VOC
content of the undiluted coating and the thinners must be calculated. The
mass of VOC in the undiluted coating is:
0.333 Ib VQC 10.25 Ib undiluted coating = 3.41 Ib VOC
Ib undiluted coating x gal undiluted coating gal undiluted coating
The mass of thinner added per gallon of undiluted coating is:
0.02 gal thinner No. 1 7.36 Ib thinner No. 1 + 0.02 gal thinner No. 2
gal undiluted coating gal thinner No. 1 gal undiluted coating
5.43 Ib thinner No. 2 + 0.01 gal thinner No. 3 9.52 Ib thinner No. 3
gal thinner No. 2 gal undiluted coating gal thinner No. 3
= 0.147 + 0.109 + 0.095 = °'351 1b thinner
gal undiluted coating
The mass VOC per volume coating at application is:
3.41 Ib VOC/gal undiluted coating + 0.351 Ib thinner/gal undiluted coating
1.05 gal coating/gal undiluted coating
= 3.58 Ib VOC/gal coating
The undiluted coating has 50.0 volume percent solids. After the coating is
diluted with 0.05 gallon of thinner per gallon of coating, the volume percent
c r* 1 T H c -i c •
solids is:
0.50 _ 0.48 gal solids
1 + 0.05 ~ volume coating
The equivalency calculations must be made on a solids basis. The formula for
determining the maximum allowable emissions on a solids basis is:
Allowable emissions = allowable mass of VOC per volume coating
(baseline TEJ (baseline volume solids)
As noted in earlier examples, an assumed VOC density of 7.36 gal is used to
calculate the volume solids content of the "presumptive" RACT coating.
The volume of VOC in the "presumptive" RACT coating is:
2.8 Ib VOC 1 gal VOC _ 0.38 gal VOC
gal coating * 7.36 Ib VOC " gal coating
24
-------
Therefore, the baseline volume of solids is:
! n ,o _ 0.62 gal solids
1 " u
-------
6.2 DETERMINING COMPLIANCE FOR A LARGE APPLIANCE COATING LINE USING SEVERAL
TYPES OF SPRAY EQUIPMENT
Example 2 -
A large appliance manufacturer has a coating operation that employs electro-
static spray coating equipment and manual spray coating equipment. The
following data are available regarding the operation. Determine the
compliance status. If the large appliance manufacturer is out of compliance,
what percent reduction is required to achieve compliance?
(A) (B)
Electrostatic Manual
coating coating
Transfer efficiency, percent 90 40
Average volume percent of solids in
coating 39 39
VOC content, Ib VOC/gal coating
less water 4.5 4.5
Gallons of coating used per day 30.4 47.1
Emission limit, Ib/gallon less 2.8 2.8
water
Baseline transfer efficiency for 60 60
large appliances, percent
The baseline transfer efficiency is 60 percent for a large appliance coater.
Table 3 is a tabulation of the available data and calculation results. The
actual calculations follow.
26
-------
TABLE 3. LARGE APPLIANCE MULTITRANSFER EFFICIENCY CALCULATION.
Spray
type
Gallons
of coat-
ing/day
Solids,
vol.
%
Lb VOC/
gallon
coating
Lb VOC/
gallon
solids
%
TE
Lb VOC/gal-
lon solids
applied
Gallons
of solids
applied/day
Pounds
of
VOC/day
Actual emissions
A
B
30.4
47.1
39
39
4.5
4.5
11.5
11.5
90
40
12.8
28.8
10.7
7.3
136.8
212.0
Total 348.8
Allowed emissions
A
B
28.8
19.6
62
62
2.8
2.8
4.5
4.5
60
60
7.5
7.5
10.7
7.3
80.6
54.9
Total 135.5
-------
Under the actual emissions category, the following calculations can be made.
For A and B, the mass of VOC per volume of solids is:
4.5 Ib VQC 1 gal coating _ 11.5 1b VOC
gal coating x 0.39 gal solids ~ gal solids
For As the mass of VOC per volume of solids applied is:
4.5 Ib VOC 1 gal coating 1 gal solids = 12.82 Ib VOC
gal coating 0.39 gal solids 0.90 gal solids applied gal solids applied
For B, the mass of VOC per volume of solids applied is:
4.5 Ib VOC 1 gal coating 1 gal solids _ 28.85 Ib VQC
gal coating 0.39 gal solids 0.40 gal solids applied ~ gal solids applied
For A, the volume of solids applied per day is:
0.90 gal
30.4 gal coating 0.39 gal solids solids applied _ 10.7 gal solids applied
day x gal coating x gal solids used day
For B, the volume of solids applied per day is:
0.40 gal
47.1 gal coating 0.39 gal solids solids applied _ 7.3 gal solids applied
day gal coating x gal solids used ~ day
For A, the mass of VOC emissions per day is:
4.5 Ib VOC 30.4 gal coating = 136.8 Ib VOC
gal coating day day
For B, the mass of VOC emissions per day is:
4.5 Ib VOC 47.1 gal coating _ 212.0 Ib VOC
gal coating day ~ day
Under the allowed emissions category, the following calculations can be made.
For A and B, the volume fraction of VOC in the baseline coating is:
2.8 Ib VOC 1 gal VOC = 0.38 gal VOC
gal coating 7.36 Ib VOC gal coating
28
-------
The volume fraction solids in the coating is:
1 . 0.38 gal VOC _ 0.62 gal solids
" "gal coating gal coating
The baseline mass of VOC per volume solids is:
2.8 Ib VOC 1 gal coating _ 4.5 Ib VOC
gal coating 0.62 gal solids ~ gal solids
For A and B, the maximum allowable emissions are:
2.8 Ib VOC 1 gal coating 1 gal solids used _ 7.5 Ib VOC
gal coating 0.62 gal solids 0.60 gal solids applied gal solids applied
The volume of solids applied remains the same. Therefore, for A, the gallons
of complying coating used per day would be:
10.7 gal solids applied 1 gal coating 1 gal solids used
day 0.62 gal solids 0.6 gal solids applied
_ 28.8 gal coating
day
For B, the gallons of complying coating used per day would be:
7.3 gal solids 1 gal coating 1 gal solids used _ 19.6 gal coating
day x 0.62 gal solids 0.6 gal solids day
applied
For A, the mass of VOC emissions allowed per day is:
2.8 Ib VOC 28.8 gal coating = 80.6 Ib VOC
gal coating day ~ day
For B, the mass of VOC emissions allowed per day is:
2.8 Ib VOC 19.6 gal coating ^ 54.9 Ib VOC
/\
gal coating day day
The total actual VOC emissions from A and B are 348.8 Ib VOC per day. The
total allowable VOC emissions are 135.5 Ib VOC per day. Therefore, the opera-
tion is out of compliance. To achieve compliance, the required reduction in
emissions is:
'348.S35'5 x 100 = 61 percent
29
-------
SECTION 7
GRAPHS AND TABLES USEFUL IN APPROXIMATING
AND DOUBLE-CHECKING SURFACE COATING CALCULATIONS
Figure 1 can be used to evaluate compliance alternatives for waterborne
and organic-borne coatings. This can be done by drawing a horizontal line
from the required VOC content of coating (less water and exempt solvents) to
the appropriate curve (depending on ratio of water to organic solvent in coat-
ing). A vertical line is then drawn from the point of intersection to the
x-axis which yields the volume percent solids. All of the coatings represent-
ed by the horizontal line have the same pounds of VOC solvent per gallon of
coating (less water and exempt solvents). A vertical line in Figure 1 from
the volume percent solids to the organic-borne line represents all of the
coatings with the same volume percent solids. Horizontal lines drawn from the
appropriate waterborne curves yield the VOC contents of the coatings less wa-
ter and exempt solvents. Note that these values are considerably different
for coatings with the same solids contents.
Figures 2 and 3 are the same graph, only Figure 2 is drawn to a larger
scale. If the pounds of VOC solvent per gallon of coating (less water and
exempt solvents) is known, these figures can be used to approximate the pounds
of VOC solvent per gallon of coating solids, assuming a solvent density of
7.36 pounds per gallon.
Table 4 presents volume percent solids equivalency data for different
coating operations. Table 5 presents CTG Equivalency Data. A VOC density of
7.36 pounds per gallon is assumed in these tables. Table 6 provides equiva-
lent solids deposited limits. Table 7 presents some useful conversion fac-
tors.
30
-------
OO
10
20 30 40 50 60
VOLUME % SOLIDS IN COATING
70"
80 90 100
Figure 1. Graph for determining equivalent solids/VOC (solvent)
contents of waterbome and organic-borne coatings.
31
-------
POUNDS OF VOC (SOLVENT) PER GALLON OF COATING
(MINUS WATER AND EXEMPT SOLVENTS)
Figure 2. Graph for determining pounds
of VOC (solvent) per gallon of coating solids.
32
-------
POUNDS OF VOC (SOLVENT) PER GALLON OF COATING
(MINUS WATER AND EXEMPT SOLVENTS)
Figure 3. Smaller-scale graph for determining
pounds of VOC (solvent) per gallon of coating solids,
33
-------
TABLE 4. CTG VOLUME PERCENT SOLIDS EQUIVALENCY DATA
Industrial finishing categories
CAN INDUSTRY
Sheet basecoat (exterior and
interior) and over-varnish;
two-piece can exterior (basecoat
and over-varnish)
Two- and three-piece can interior
body spray, two-piece can exteri-
or end (spray or roll coat)
Three-piece can side-seam spray
End sealing compound
COIL COATING
Prime and topcoat or single coat
operation
FABRIC COATING
Fabric coating line
Vinyl coating line
PAPER COATING
Coating line
AUTOMOTIVE AND LIGHT-DUTY TRUCK
ASSEMBLY PLANT
Primer (electrodeposited) applica-
tion, flashoff area and oven
Surfacer (guide-coat) application,
flashoff area and oven
Topcoat application, flashoff
area and oven
Kg VOC
per liter
of coating
less water
0.34
0.51
0.66
0.44
0.31
0.35
0.45
0.35
0.14
0.34
0.34
Lb VOC
per gallon
of coating
less water
2.8
4.2
5.5
3.7
2.6
2.9
3.8
2.9
1.2
2.8
2.8
Solvent-borne
coating
equivalent
volume % solids
62.0
42.9
25.3
49.7
64.7
60.6
48.4
60.6
83.7
62.0
62.0
(continued)
34
-------
TABLE 4. (continued)
Industrial finishing categories
AUTOMOTIVE AND LIGHT-DUTY TRUCK
ASSEMBLY PLANT (continued)
Final repair application,
flashoff area and oven
METAL FURNITURE
Coating line
MAGNET WIRE INSULATION
Wire coating oven
LARGE APPLIANCES
Prime, single, or topcoat
application area, flashoff
area and oven
MISCELLANEOUS METAL PARTS
Air-dried items
Clear-coated items
Frequent-color-change items
Powder-coated items
Extreme performance coatings
Kg VOC
per liter
of coating
less water
0.58
0.36
0.20
0.34
0.42
0.52
0.36
0.05
0.42
Lb VOC
per gallon
of coating
less water
4.8
3.0
1.7
2.8
3.5
4.3
3.0
0.4
3.5
Solvent-borne
coating
equivalent
volume % solids
34.8
59.2
76.9
62.0
52.4
41.6
59.2
94.6
52.4
35
-------
TABLE 5. CT6 EQUIVALENCY DATA (VOC DENSITY = 7.36 LB/GAL)
Industrial finishing categories
Can Industry
Sheet basecoat (exterior and interior)
and over-varnish; two-piece can ex-
terior (base-coat and over-varnish)
Two- and three-piece can interior body
spray, two-piece can exterior end
spray or roll coat
Three-piece can side-seam spray
End sealing compound
Coil Coating
Prime and topcoat or single coat op-
eration
Fabric Coating
Fabric coating line
Vinyl coating line
Solvent-
borne
coating
equivalent
volume %
solids
62.0
42.9
25.3
50.3
64.7
60.6
48.4
Lb VOC
per gallon
of coating
less water
2.8
4.2
5.5
3.7
2.6
2.9
3.8
Kg VOC
per liter
of coating
less water
0.34
0.51
0.66
0.44
0.31
0.35
0.45
Lb VOC
per gallon
of solids
4.5
9.8
21.7
7.4
4.0
4.8
7.9
Kg VOC
per liter
of solids
0.55
1.19
2.61
0.88
0.48
0.58
0.93
co
en
(continued)
-------
TABLE 5. (continued)
Industrial finishing categories
Paper Coating
Coating line
Automotive and Light-Duty Truck
Assembly Plant
Primer (electrodeposition) application,
flashoff area and oven
Surfacer (guide coat) application,
flashoff area and oven
Topcoat application, flashoff area and
oven
Final repair application, flashoff
area and oven
Metal Furniture
Coating line
Magnet Wire Insulation
Wire coating oven
Solvent-
borne
coating
equivalent
volume %
solids
60.6
83.7
62.0
62.0
34.8
59.2
6.9
Lb VOC
per gallon
of coating
less water
2.9
1.2
2.8
2.8
4.8
3.0
1.7
Kg VOC
per liter
of coating
less water
0.35
0.14
0.34
0.34
0.58
0.36
0.20
Lb VOC
per gallon
of solids
4.8
1.4
4.5
4.5
13.8
5.1
2.2
Kg VOC
per liter
of solids
0.58
0.17
0.55
0.55
1.67
0.61
0.26
GJ
(continued)
-------
TABLE 5. (continued)
Industrial finishing categories
Large Appliances
Prime, single, or topcoat application
area, flashoff area and oven
Miscellaneous Metal Parts and Products
Air-dried items
Clear-coated items
Frequent-color-change items
Powder-coated items
Extreme performance coatings
Solvent-
borne
coating
equivalent
volume %
solids
62.0
52.4
41.6
59.2
95.6
52.4
Lb VOC
per gallon
of coating
less water
2.8
3.5
4.3
3.0
0.4
3.5
Kg VOC
per liter
of coating
less water
0.34
0.42
0.52
0.36
0.05
0.42
Lb VOC
per gallon
of solids
4.5
6.7
10.3
5.1
0.4
6.7
Kg VOC
per liter
of solids
0.55
0.80
1.25
0.61
0.05
0.80
CO
00
-------
TABLE 6. EQUIVALENT CTG SOLIDS DEPOSITED LIMITS
Auto and Light-duty Truck*
Surfacer
Topcoat
Metal Furniture
Coating line
Large Appliances
Coating Line
Lb/gal-H,0
(kg/1)
2.8
(0.34)
2.8
(0.34)
3.0
(0.36)
2.8
(0.34)
Volume % Solids
62.0
62.0
59.2
62.0
Baseline T.E.
30
30
60
60
Lb/gal solids deposited
(kg/1)
15.1
(1.83)
15.1
(1.83)
8.4
(1.01)
7.5
(0.91)
*Waterborne equivalence
-------
TABLE 7. METRIC CONVERSION FACTORS
Metric
abbrevation
kg
liter
Mg
MT
dscm
scmm
Metric unit
kilogram (103 grams)
liter
megagram (106 grams)
metric ton (106 grams)
dry standard cubic meters
standard cubic meter per min
Equivalent
English unit
2.2046 Ib
0.2642 gal, 0.353 ft3
2,204.6 Ib
2,204.6 Ib
35.31 dry St. ft3
35.31 ft3/min
B. Multiply Ib/gal x 0.12 to get kg/liter
C. Multiply kg/liter x 8.34 to get Ib/gal
D. Temperature: Degrees Celsius or centigrade (°C) can be converted to
degrees Fahrenheit (°F) by the following forumla:
t°F = 1.8 (t°C) + 32
40
-------
REFERENCES
1. "Compliance with VOC Emission Limitations for Can Coating Operations,"
45 FR 80824, dated December 8, 1980.
2. "Glossary for Air Pollution Control of Industrial Coating Operations."
Second Edition. Emission Standards and Engineering Division, U.S. Envi-
ronmental Protection Agency. EPA-450/3-83-013R. December 1983.
3. Memorandum entitled "Appropriate Transfer Efficiencies for Metal Furni-
ture and Large Appliace Coating," from G.T. Helms, Chief, Control Pro-
grams Operations Branch, to Chief, Air Programs Branch, Regions I-X,
dated November 28, 1980.
4. Memorandum entitled "Appropriate Transfer Efficiency for Water-Borne
Equivalence," from R.G. Rhoads, Director, Control Programs Development
Division to Director, Air and Hazardous Materials Division, Regions I-X,
dated July 3, 1979.
5. Memorandum entitled "Determination of Capture Efficiency," from J. Berry,
Chief, Chemical Analysis Section, to D. Cook, EPA Region IV, dated July
7, 1980.
6. Memorandum entitled "Equivalency Calculations with the CTG Recommenda-
tions for Surface Coating," from R.G. Rhoads, Director, Control Programs
Development Division, to David Kee, Director, Air and Hazardous Materials
Division, Region V, dated October 17, 1980.
7- Memorandum entitled "Procedure to Calculate Equivalency with the CTG
Recommendations for Surface Coating, from R.G. Rhoads, Director,
Control Programs Development Division, to Chief, Air Programs Branch,
Regions I-X, dated May 5, 1980.
8. Memorandum entitled "RACT Options for Can Coating Operations," from R.G.
Rhoads, Director, Control Programs Development Division to Director, Air
and Hazardous Materials Division, Regions I-X, dated November 21, 1978.
9. Memorandum entitled "Role of Improved Transfer Efficiency in Demonstrat-
ing Compliance with the CTG Recommendations for Surface Coating", from
G.T. Helms, Chief, Control Programs Operations Branch, to W.S. Baker,
Chief, Air Programs Branch, Region II, dated December 2, 1980.
41
-------
10. "Procedures for Certifying Quantity of Volatile Organic Compounds Emitted
by Paint, Ink, and Other Coatings." Emission Standards and Engineering
Division, U.S. Environmental Protection Agency. EPA-450/3-84-019. De-
cember 1984.
-------
APPENDIX A
GLOSSARY OF TERMS USED IN
AIR POLLUTION CONTROL OF EMISSIONS
FROM INDUSTRIAL COATING OPERATION
EPA PUBLICATION NO. 450/3-83-013R, PAGES 26-29
A-l
-------
A-2
-------
° HOW MUCH COATING IS NEEDED TO DO A PARTICULAR JOB?
The same volume of coating solids must be deposited on an object
to coat it to a desired film thickness regardless of the type of
coating or volatile organic compound content of the coating used.
Solids make the film. Volatiles (VOC. water, and non-photochemlcally
reactive solvents) evaporate.
Four gallons of a 25 volume percent (v/o) solids coating must be
used to get one gallon of coating sol Ids.
But, only two gallons of a 50 v/o solids coating must be used to get
one gallon of coating solids.
26
This means that twice as much work can be done with a gallon of
50 v/b~"sb1ids coating than with a gallon of Zb v/o sonds coating.
Twice as many gallons of 25 percent solids coating are needed than
gallons of 50 percent sol Ids coating to do the same Job.
e HOW DO EMISSIONS FROM DIFFERENT COATINGS COMPARE?
Comparisons of the percent difference 1n emissions between two
coatings, or between a coating and an emission limit, must be done on
a solids basis.
VOC.
Each gallon of the 25 v/o solids coating contains 5.5 pounds of
So, for each gallon of coating solids, 22.0 pounds of VOC are
emitted.
5.5 pounds VOC
gallon coating
4 gallons coating
gallon solids
Each gallon of the 50 v/o solids coating contains 3.7 pounds
of VOC.
27
-------
So, for each gallon of coating solids, 7.4 pounds of VOC are
emitted.
3.7 pounds VOC
gallon coating
2 gallons coating
gallon solids
Thus, emissions from the 50 v/o solids coatings are 66 percent
less than from the 25 v/o solids coating when providing an equal
amount of solids to the process.
22.0-7.4
0.66
0 WHAT EMISSION REDUCTION IS NEEDED TO MEET AN EMISSION LIMIT?
This calculation, which must also be done on a solids basis,
is the same as that used above Eo compare emi ssions from two
different coatings.
A coater who uses a 25 v/o solids coating containing 5.5 pounds
of VOC per gallon, less water, must reduce emissions by 66 percent
to meet an emission limit of 3.7 pounds of VOC per gallon,
less water.
HOW MUCH DO IMPROVEMENTS IN TRANSFER EFFICIENCY HELP A SOURCE TO
COMPLY?
The coater may want to use a coating that does not comply with a
regulation and compensate by improvements in the transfer efficiency
with which the coating is applied to meet an equivalent emission
level. In order to calculate credit for VOC reductions which result
from improvements in transfer efficiency, calculations should be done
using units of:
Ib VOC
gallon solids deposited
These units are determined by dividing Ib VOC/gallon solids by
the transfer efficiency expressed as a decimal fraction. For
example, if the starting transfer efficiency is 60 percent, the units
would be:
1.0 gal solids
in coating used
Ib VOC
gal solids deposited
(with the old system)
Ib VOC
gal solids
in coating used
U.6U gal solids
deposited
28
If the same paint were now to be sprayed with 90 percent
transfer efficiency, the new value would he:
Ib VOC
1 b VOC
gallon solids
in coating used
1.0 gal solids
in coating used
0.90 gal solirls
deposited
gallon solids
deposited
(with new s'ystem)
If both the solvent content of the coating and the transfer
efficiency are changed, the situation becomes:
1.0 gal solids in
j new coating used
T gal solids
deposited
Ib VOC
Ib VOC
gal solids deposited
(with new paint and
new transfer efficiency)
gal soiids in
new coating
used
where j = the new transfer efficiency expressed as a decimal
Expressed in these units, the emissions from the old and new
systems can be directly compared to determine the reduction achieved.
NOTE: For 'metal furniture and appliance coating, the EPA has
recommended* that credit for transfer efficiency be given from a base-
line of 60 percent transfer efficiency (TE). For example, if a
company goes from 35 percent TE to 85 percent TE, credit should only
be given for going from 60 percent TE to 85 percent TE to avoid
rewarding a source that has historically had poor transfer efficiency
- hence a high emission rate.
The rationale for this is that 60 percent TE is a reasonable
transfer efficiency to achieve for these industries, and credit
should only be given for exceeding 60 percent TE.
For the automobile industry, the CTG recommendation for baseline
transfer efficiency is 30 percent TE for both primer surfacer and
topcoat. This is the efficiency at which waterborne coatings were
applied at two existing assembly plants.
* Memo froni G. T. Helms, Chief, Control Programs Operations Branch,
EPA, to Chief, Air Programs Branch, EPA Regions I-X, "Appropriate
Transfer Efficiencies for Metal Furniture and Large Appliance
Coating", November 23, 1980.
29
-------
APPENDIX B
PROCEDURES FOR CERTIFYING QUANTITY OF
VOLATILE ORGANIC COMPOUNDS EMITTED
BY PAINT, INK, AND OTHER COATINGS
B-l
-------
-------
United States Office of Air Quality EPA-450/3-84-019
Environmental Protection Planning and Standards December 1984
Agency Research Triangle Park NC 27711
Air
&EPA Procedures for
Certifying
Quantity of
Volatile Organic
Compounds
Emitted by Paint,
Ink, and Other
Coatings
NOTICE
THIS EDITION INCLUDES PAGES III-4
AND III-9 AS REVISED JUNE 19,1986
-------
EPA-450/3-84-019
Procedure for Certifying Quantity of
Volatile Organic Compounds Emitted
By Paint, Ink, and Other Coatings
Emission Standards and Engineering Division
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Air and Radiation
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711
December 1984
-------
This report has been reviewed by the Emission Standards and Engineering Division of the Office of Air Quality
Planning and Standards, EPA, and approved for publication. Mention of trade names or commercial products is not
intended to constitute endorsement or recommendation for use. Copies of this report are available through the
Library Services Office (MD-35), U.S. Environmental Protection Agency, Research Triangle Park, N.C. 27711, or
from the National Technical Information Services. 5285 Port Royal Road, Springfield, Virginia 22161.
ti
-------
PREFACE
This manual was conceived as a way to provide simple step-by-step
instructions for certifying the quantity of volatile organic compounds
(VOC) that will be released by a coating. It has not turned out that
way. The guidance is here, but in spite of great diligence, the
instructions remain imposing.
The manual was prepared for several reasons. First, the coatings
industry, as represented by the National Paint and Coatings Association,
had requested a certification procedure which would relieve their custom-
ers the expense of analysis. Second, the complexity of the calculations
necessary to determine compliance, for example, when dilution solvent is
added to a coating, continue to confound Federal, State and Local enforce-
ment personnel. Finally, results of a recent review of the Agency's
reference method for determining VOC reemphasized the importance of
analytical procedures to verify VOC content.
In response to the results of the review of the test methods, this
manual reaffirms that Reference Method 24 or its constituent methods
developed by the American Society for Testing and Materials (ASTM),
are the procedures by which the VOC content of a coating will be deter-
mined for compliance with Federal regulations. The earliest guidance
was not so specific. In 1977, the first report*, written to assist
States in developing regulations for sources of VOC emissions, provided
recommendations for the maximum allowable VOC content for complying
coatings in a variety of industries. These values were expressed in
mass of VOC per unit volume of coating. In deriving the recommended
limitation, the VOC content of a coating was calculated based on the
solids content provided by the coating manufacturer. The Agency calcu-
lated the mass of VOC in the coating by assuming the YOC had a density
of 7.36 pounds per gallon.
Solvent and VOC were used somewhat interchangebly even though it
was recognized that organics such as resin monomer, oligimers, and
reaction by-products could be released by a coating during the cure.
There was no accepted analytical method available for measuring the
total VOC which would be released by a coating. The initial guidance*
provided an analytical method for use only for air-dry coatings, those
where all VOC emissions would be expected to come as a result of evapor-
ation of solvent. On a volume basis, air dry coatings constituted the
largest catagory of coatings then in use.
The Agency subsequently developed a more general analytical proce-
dure that could be used to determine the total YOC in a coating. On
October 3, 1980, the Agency published "Reference Method 24 (RM-24) -
Control of Volatile Organic Emissions from Stationary Sources -
Volume II: Surface Caoting of Cans, Coils, Paper, Fabrics, Automobiles,
and Light-duty Trucks, Document No. EPA-450/2-77-008.
m
-------
Determination of Volatile Matter Content, Density, Volume Solids, and
Weight Solids of Surface Coatings," in the Federal Register (45 FR 65958).
For the first time the Agency formally specified an analytical method
for the VOC content of those coatings that cure by chemical reaction.
Even then, the announcement continued to allow the manufacturer's formu-
lation to be used to calculate the VOC content but specified that the
analytical technique, RM-24, woul d be the reference in any conflict
between the two.
During 1981 and 1982, as more State and Federal regulations were
established, the demand for low-solvent coatings began a continuing
increase in the sales volume of reaction-cure coatings. There was some
concern voiced by the industry in how appropriate the reference method
was for these type coatings. To find out, the Agency began a review of
RM-24 to determine the effect of temperature and exposure time on the
indicated VOC "content". It was concluded that the maximum effect of
those time-temperature combinations that were examined amounted to only
about a 10 percent variation. Somewhat more surprising was that the
solvent sometimes accounted for only 50 to 70 percent of the total
VOC measured by the reference method.
The obvious conclusion was that RM-24 is a better measure of the
total organics freed by a coating than is the solvent. This manual
implements a policy based on that conclusion. Certification of VOC
content on the attached Data Sheets must be based on an analysis using
RM-24. No longer will solvent content be permitted as a surrogate for
VOC unless a showing is first made that its use is a reasonable alter-
native or equivalent method of determining the VOC content of that
particular coating.
One final comment. Since VOC is not always synonomous with solvent,
it follows that the amount of solids in a coating cannot be obtained by
subtracting the solvent from the total volume of coating. The original
Federal Register proposal for RM-24, published on October 3, 1980, recom-
mended the American Society of Test Materials test Number D2697 as the
appropriate method of determining solids content. Subsequent comments
from the industry maintained that this test is unreliable. As a result,
when promulgated in 1980, RM-24 specified that the solids content of a
coating can be obtained only from the manufacturer's formulation of the
coating.
Dennis Crumpler
December 14, 1984
IV
-------
TABLE OF CONTENTS
CHAPTER Page
PREFACE 111
GLOSSARY OF TERMS AND SYMBOLS vi
1 INTRODUCTION 1-1
2 -VOC CONTENT OF PAINT, INK, AND OTHER COATINGS
"AS SUPPLIED" BY THE COATING MANUFACTURER II-l
2.1 VOC DATA SHEET FOR "AS SUPPLIED" COATINGS .... 11-2
2.2 IMPLEMENTING INSTRUCTIONS 11-3
3 VOC CONTENT OF PAINT, INK AND OTHER COATINGS
"AS APPLIED" TO THE SUBSTRATE BY THE USER III-l
3.1 VOC DATA SHEET FOR "AS APPLIED" COATINGS II1-2
3.2 IMPLEMENTING INSTRUCTIONS III-4
-------
GLOSSARY OF TERMS
"As Applied" the condition of a coating after dilution by the user
just prior to application to the substrate.
"As Supplied" the condition of a coating before dilution, as sold
ana delivered by the coating manufacturer to the user.
(Dc)a coating density "as applied"
(Dc)s coating density, "as supplied"
Dj density of dilution solvent
D^ density of organic solvent/water mixture
Dw density of water (8.33 Ib/gal)
Rd dilution solvent ratio, equals the volume of VOC added
per unit volume of coating "as supplied"
Rdt equals the voluue of premixed water and VuC added per
unit volume of coating "as supplied"
(Vn)a Volume percent solids of coating "as applied"
(Vn)s Volume percent solids of coating "as supplied"
(VOC)a VOC content of "as applied" coating, expressed as mass
of VOC per unit volume of coating less water or as mass
of VuC per unit volume of solids
(VOC)S VOC content of "as supplied" coating, expressed as mass
of VOC per unit volume of coating less water or as mass
of VOC per unit volume of solids
(Vw)a the water content, in volume percent, of coating "as applied"
(Vw)d the water content, in volume percent, of the dilution solvent
added to the "as supplied" coating
(Vw)s the water content, in volume percent, of the coating
"as supplied"
(W0)a the organic volatile content, in weight percent, of the
coating "as applied"
(W0)s the organic volatile content, in weight percent, of the
coating "as supplied"
VI
-------
(Wv)a the weight percent of total volatiles in the coating
"as applied"
(Wv)s the weight percent of total volatiles in the coating
"as supplied"
(Ww)a the weight percent water in the coating "as applied"
(Ww)
-------
1. INTRODUCTION
This Manual provides step-by-step instruction for preparation of two
data sheets developed by the Environmental Protection Agency which may be
used by coating manufacturers and users to present information on the
quantity of volatile organic compounds* (VOC) emitted from a coating.
One of the data sheets may be prepared by the manufacturer of the coating;
the second would be used by the company that applies the coating to a
substrate.
The first VOC data sheet, which would be prepared by the manufacturer,
provides information on the volatile organic content of a coating as it is
delivered to a customer. This is referred to as the VOC content of the
coating "as supplied" (by the manufacturer to the user).
The second VOC data sheet, which would be prepared by the user or coater,
provides information on the quantity of volatile organic compounds present as
the coating is used or applied to the substrate and includes the effect
of any dilution solvent added before application. This is referred to as the
VOC content of the coating "as applied" (to the substrate).
The coating user may submit, and the Agency enforcing a regulation may
accept, these data sheets as prima facie evidence of the actual VOC content
of a coating. The referee method for ultimate determination of compliance,
however, will continue to be the method specified in the applicable regula-
tion (for example, LPA Reference Method 24 or individual AbTM methods).
*Volatile Organic Compound (VOC) - Any organic compound which participates
in atmospheric photochemical reactions; that is, any organic compound
other than those whicn the Administrator designates as having negligible
photochemical reactivity. VOC may be measured by a reference method,
an equivalent method, an alternative method, or by procedures specified
under any regulation.
1-1
-------
2. VOC CONTENT OF PAINT, INK AND OTHER COATINGS
"AS SUPPLIED" BY THE COATING MANUFACTURER TO THE USER
II-l -
-------
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
VOC DATA SHEET:
PROPERTIES OF THE COATING "AS SUPPLIED" BY THE MANUFACTURER
Coating Manufacturer:
Coating Identification:
Batch Identification:
Supplied To:
Properties of the coating as supplied^ to the customer:
A. Coating Density (Dc)s : _ Ib/gal _ kg/1
I 7 ASTM D147b / J Other2
B. Total Volatiles (Wv)s : _ Weight Percent
ASTM D2369 f~T Otner2
C. Water Content: 1. (Ww)s _ Weight Percent
ASTM D3792 /~7 ASTM D4017 ~ Other2
2. (Vw)s _ Volume Percent
/ 7 Calculated / 7 Other?
u. Organic Volatiles (WQ)S : _ Weight Percent
£. Nonvolatiles Content (Vn)s : _ Volume Percent
F. VOC Content (VOC)S: 1. _ Ib/gal coating less water
or _ kg/1 coating less water
2. _ Ib/gal solids
or _ kg/1 solids
Remarks: (use reverse side)
iThe subscript "s" denotes each value is for the coating "as supplied"
by the manufacturer.
2Explain the other method used under "Remarks".
Signed:
II-2 '
-------
2.2 IMPLEMENTING INSTRUCTIONS FOR THE VOC DATA SHEET FOR "AS SUPPLIED" COATINGS
This UATA SHEET is normally completed by the coating manufacturer and
provided to the user.l It will henceforth be referred to as the "AS SUPPLIEu"
VUC UATA SHEET.
A. The "as supplied" coating density, (Dc)s^, is determined using
"ASTM J1475 - Standard Test Method for Density of Paint, Lacquer,
and Related Products."
B. The weight percent of total volatiles in a coating, (Wv)s, is determined
by "ASTM u23b9 - 81 Standard Method for Volatile Content of Coatings."
drying conditions to be used are 11G°C for 1 hour3.
C. Water Content
1. The weight percent water, (Ww)s, is determined by "ASTM D3792 -
Standard Test Method for Water Content of Water-Reducible Paints
by Direct Injection Into a bas Chromatograph," or "ASTM 1)4017 -
Standard Test Metnod for Water in Paints and Paint Materials by
the Narl Fischer Method."^ An acceptable alternative to thtse
procedures for purposes of preparing the data sheet would be to
calculate the weight percent water from the manufacturer's coating
formulation.
lEPA's Reference Method 24 (40 C.F.R. Part faO, App. A), contains the
ASTM methods referenced in these instructions.
2The subscript "s" denotes those parameters of a coating when measured
in the "as supplied" condition, before dilution by the user.
3If the manufacturer believes a specified method does not give results
that are representative of the actual cure mechanism, he may petition the
enforcement authority for approval of an alternate analytical method. Any
alternate method or alteration to the methods and procedures in these instruc-
tions or in any applicable regulation would be subject to review and approval
by the appropriate State and Federal enforcement agency.
^Volatile compounds classified by EPA as having negligible photochemical
reactivity such as 1,1,1-trichloroethane and methylene chloride, etc., and
listed as exempt in the applicable Federal and State VOC regulation should
be treated in the same manner as water. The weight percent.of negligibly
reactive compounds in a coating should be determined from the manufacturer's
formulation. The volume percent can then oe calculated using equation II-l
when the weight percent and density of the negligibly reactive compounds are
substituted for those of water. The weight and volume percent can be used in
Equations II-2 and 11-6, respectively, in place of (Ww)s and (Vw)s.
II-3
-------
2, The water content, in volume percent, (Yw)s, can be calculated
by the equation:
where Dw is the density of water, 8.33 Ibs/gal.
D. The organic volatiles content, (W0)s, i.e., the VOC content
expressed as a percent by weight, is determined by the following
equation^:
(W0)s = (Wv)s -
-------
F. The VOC content of the "as supplied" coating (VOC)S can now be calculated
and thereby expressed in terms used by most State or Federal regulations.
1. The mass of VOC per unit volume of coating less water:
a. If the coating contains no water, the equation is calculated
as follows:
ruos
b. If the coating contains water, Equation II-5 becomes:
(VOC) .
'
1001 -
2. The VOC content may also be calculated in terms of mass of VOC per
unit volume of solids (nonvolatiles). For both solvent-borne and
waterborne coatings, the equation is:
(VOC)s =
(DcJs M-7
II-5 .
-------
3. VOC CONTENT OF PAINT, INK AND OTHER COATINGS
"AS APPLIED" TO THE SUBSTRATE BY THE USER
ni-i
-------
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
VOC DATA SHEET:
PROPERTIES OF THE COATING "AS APPLIED" TO THE SUBSTRATE
Coating Manufacturer:
Coating Identification:
Batch Identification:
User:
User's Coating Identification:
Properties of the coating as applied1 by the User:
A. Coating Density (Dc)a: kg/1, or Ib/gal
/ 7 ASTM D1475 f~7 Other2
B. Total Volatiles (Wv)a: Weight Percent
/~7 AS™ D2369
r~T Other2
C. Water Content: 1. (Ww)a
/7 ASTM D3792 f~7 ASTM D4017 / J Other2
2- (Vw)a
I 7 Calculated
Other2
Weight Percent
Volume Percent
D. Weighted Average Density of the dilution solvent (Dd)3:
/~7 ASTM D1475 l~~l Handbook f~7 Formulation
Ib/gal
(Continued on Reverse Side)
iThe subscript "a" denotes each value is for the coating "as applied" to the
substrate.
2Explain the other method used under "Remarks" on reverse side
JThe subscript "d" denotes values are for the dilution solvent
III-2
-------
Dilution Solvent Ratio (Rj):
or
gal diluent
(gal coating)
liter diluent
F.
G.
H.
Organic Volatiles Content (WQ)a:
Non-Volatiles Content (Vn)a:
VOC Content (VOC);,: 1. -
(1
Ib/gal of
Her coating) 4
Weight Percent
Volume Percent
coating less water
or
2.
or
kg/1 of coating less water
Ib/gal solids
kg/1 solids
REMARKS:
Signed:
Date:
4The subscript "s" denotes values are for the coating "as supplied" by the
manufacturer.
5This terminology is used to be consistent with Method 24. It refers to
all photochemically reactive oryanic compounds emitted from the coating
including reactive by-products of the cure reaction, exactly the same
matter as indicated in Paragraph H, i.e., volatile organic compounds,
or VOC.
III-3
-------
PAGE REVISED JUNE 19, 1986
3.2. IMPLEMENTING INSTRUCTIONS FOR THE VOC DATA SHEET FOR "AS APPLIED" COATINGS
This DATA SHEET, henceforth referred to as the "AS APPLIED" VOC DATA
SHEET, is to be completed by the company which applies a coating. It
provides information on the amount of volatile organic compounds (VOC) in
the coating "as applied" to the substrate by accounting for the quantity of
diluent solvent added to the "as supplied" coating prior to application.
If a coating is diluted only with water or a solvent of negligible photo-
chemical reactivity, the user merely doucments the fact (see Step E.I. and
also Footnote 4, Pg. III-5.). Otherwise, several avenues exist for the
coater to certify the VOC content:
(1) Maintain adequate records of how much organic solvent is added to each
coating and use that information and the "AS SUPPLIED" VOC DATA SHEET2 to
calculate the VOC content "as applied." In this case begin with Step D.
(2) If the "AS SUPPLIED" DATA SHEET is available, but dilution records are
not, begin the "As Applied" determination with Step A, skip Steps B and C,
and proceed to Step D.
(The user may choose to analyze an "As Supplied" coating using Reference
Method 24 and complete the "AS SUPPLIED" VOC DATA SHEET rather than have
the coating manufacturer complete it. The volume percent solids, however,
will necessarily continue to be supplied by the coating manufacturer.)
(3) Analyze each diluted coating with the same method used to generate the
data provided by the coating manufacturer on the "AS SUPPLIED" VOC DATA
SHEET. (See Chapter 2 of this Manual.) In this case begin with Step A.1
A. The "as applied" coating density, (Dc)a , is determined using "ASTM D1475-
Standard Test Method for Density of Paint, Lacquer, and Related Products."
B. The weight percent of total volatiles in the coating, (Wv)a is determined
by "ASTM 02369-81 Standard Method for Volatile Content of Coatings."
The drying conditions to be used are 110°C for 1 hour3.
iEPA's Reference Method 24 (40 C.F.R. Part 60, App. A), contains the
ASTM methods referenced in these .instructions.
^The subscript "a" denotes those parameters of a coating in the
"as applied" condition, i.e., after dilution by the user. The subscript
"s" denotes the parameters of a coating in the "as supplied" condition,
before dilution by the user.
3If the manufacturer believes the specified method gives results that
are not representative of the VOC released during the normal cure, he
may petition the enforcement authority for approval of an alternative
analytical method. Any alternate method or alteration to the methods
and procedures in these instructions or in any applicable regulation
would be subject to review and approval by the appropriate State and/or
Federal enforcement agency.
III-4
-------
C. The water content is necessary only if the coating has been diluted
with a" mixture of organic solvent and water. 4, 5 if the dilution
solvent is 100 percent organic, or if the weight and volume percent
water in the mixture is known, proceed directly to Step D.
The weight percent water, (Ww)a, is determined by "ASTM U3792 -
Standard Test Method for Water Content of Water-Reducible
Paints by Direct Injection Into a Gas Chroma tograph," or "ASTM D4017
- Standard Test Method for Water in Paints and Paint Materials by
the Karl Fischer Method." (Also see Footnote 3, Pg. III-4.)
The water content, in volume percent, (Vw)a, can be calculated by
the equation:
- 'Va 'Dc'. Ill-i
where bw is the density of water, 8.33 Ib/gal.
^Volatile compounds"classified by EPA as having negligible photochemical
reactivity such as 1,1,1-trichloroethane and methylene chloride, etc., and
listed as exempt in the applicable Federal and State VuC regulation, should
be treated in the same manner as water. The weight percent of negligibly
reactive compounds in the dilution solvent must be known either from the
coater's mixing records or the dilution solvent supplier's formulation.
The volume percent can then be calculated using Equations 1II-1 or III-5
when the weight percent and density of the negligibly reactive organics
are substituted for those of water. The weight and volume percent of
the negligibly reactive compounds can be substituted in all equations
where the weight and volume percent water, (Ww) and (Vw), respectively,
are used.
5The precision limit adjustments permitted by Reference Method 24 for
experimentally determined mean weight percent water and total volatiles,
kw and *v respectively, may be made only by enforcement agencies tor
determination of compliance. The adjustment is not to be used for the
purposes of completing the "AS APPLIED" VUC
III-5
-------
D. If the dilution solvent consists of a single compound the density
may be obtained from the literature.
If the dilution solvent is a mixture of organic compounds, the
density, Ddb, can be determined analytically via Ai>TM uK75, or
an average density can be estimated from the solvent formulation
as shown below. This estimation assumes that volumes are additive,
Q 100%
d
m W, IH-2
or
m
III-3
where: Dj, Wj, and V, denote the density, weight percent,
and volume percent or each solvent in the dilution solvent
mixture and "m" is the number of organic solvents in the
dilution solvent mixture.
If the dilution solvent is a mixture of photocneuically reactive
organics and water, the coater must know the weight percent, (Wy/)^,
or volume percent, (Vw)d "df IH-5
uw
where "Dw" is the density of water.
6The subscript "d" denotes a parameter that pertains to that solvent
used by the coater to dilute the "as supplied" coating.
III-6
-------
E. The dilution solvent ratio, R^, is defined as the volume of
photochemically reactive organic solvent, (VOC), added per unit
volume of "as supplied" coating. Stated mathematically-.
R = Volume photochenrically reactive dilution solvent added
d Volume of "as supplied" coating
1. If the "as supplied" coating is subsequently diluted with
water or a solvent which is of negligible photochemical
reactivity, the VOC content will be unchanged from that reported
on the "AS SUPPLIED" VOC UATA SHEET. This should be reported on
the "AS APPLIED" VOC DATA SHEET by entering "0" for the dilution
solvent ratio, R^.
2. In the absence of adequate dilution records, R,j can be
calculated from entries on the VOC UATA SHEETS by one of the
following equations:
a. When the dilution solvent consists only of VOC,
s - (Oc)a III-6
a _
d "
- iudy
b. When the dilution solvent is a mixture of water and
photochemical ly reactive organic solvent, Equation IiI-6
may be expressed as:
where: k^ is the ratio of the volume of water
and organic dilution solvent to the volume of "as
supplied" coating to which it is added. (Also see
Footnote 4, Pg. III-5.)
The dilution solvent ratio, K
-------
F- The organic volatile content (W0)a, i.e. the YOC content expressed
as a percent by weight of the diluted coating, can now be calculated
by either of two ways:
1. From analyses of the coating using the following equation:
(W0)a =
-------
PAGE REVISED JUNE 19, 1986
. (2). If the coating contains water the following equation
must be used:
(VOC) = (U'°)a (°c)a 111-14
V ;a -UU* - (Vw)a
b. Using the VOC content of the "as supplied" coating, (VOCS),
the dilution solvent ratio, and the density of the solvent,
the equation is:
_ L(VOC)S (100% - (Vw)s)/100%] + (RdDd) HI-15
3 " 1 + Rd - (VW)S/10U%
Where (VOC)S in this case must be in units of
Ibs VOC/gal coating .less water.
2. The VOC content may also be calculated in terms of mass of VOC
per unit volume of solids (nonvolatiles).
a. Using the results obtained by analyzing the coating with EPA
Reference Method 24 or its constituent ASTM methods,
the equation for both solvent-borne and waterborne coatings,
is:
(VOC) = (W°!a (Dc)a 111-16
b. Using dilution information and calculation procedures only,
the equation is:
_ C(voc)5 (100% - (vw)5)/ioo%3 + (Rdod) in-17
1 a (vn)s/iuu%
Where (VOC)S in this case must be in units of
Ibs VOC/gal coating less water.
III-9
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
i. REPORT NO.
EPA 450/3-84-019
3. RECIPIENT'S ACCESSION NO.
\. TITLE AND SUBTITLE
Procedures for Certifying Quantity of Volatile Organic
Compounds Emitted by Paint, Ink, and Other Coatings
5. REPORT DATE
December 1984
6. PERFORMING ORGANIZATION CODE
7. AUTHOH(S)
8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Office of Air Quality Planning and Standards
U. S. Environmental Protection Agency (MD-13)
Research Triangle Park, NC 27711
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
13. TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
EPA/200/04
15. SUPPLEMENTARY NOTES
16. ABSTRACT
This manual provides procedures by which firms may voluntarily
certify the quantity of volatile organic compounds which will be emitted
by a paint, ink, or other coating. Two data sheets are provided. One
is to be used by the manufacturer of the coating, the other by the user.
Analytical test methods and procedures for preparing the data sheets are
included, as are the equations and instructions necessary to convert the
analytical results into a format suitable for determining compliance with
State or Federal regulations.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
D.IDENTIFIERS/OPEN ENDED TERMS
COSATl Field/Croup
Air Pollution
Coatings
Compliance Calculations
Pollution Control
Reference Method 24
Test Methods
Volatile Organic Comoounds
Air Pollution Control
13-B
19. SECURITY CLASS (This Report/
Unclassified
!0. SECURITY CLASS /This pa?e;
Unclassified
21. NO. OF PAGES
15
22. PRICE
EPA Form 2220-1 (Rev. 4-77)
PREVIOUS EDITION IS OBSOLETE
-------
APPENDIX C
REFERENCE METHOD
C-l
-------
C-2
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Pt. 60, App. A, M«th. 24
Title 40—Protection of Environment
METHOD 24—DETERMINATION or VOLATILE
MATTER CONTEND WATER CONTENT. DENSI-
TY, VOLUME SOLIDS, AND WEIGHT SOLIDS or
SURTACE COATINGS
1.1
1. Applicability and Principle
Applicability. This method applies to
the determination of volatile matter con-
tent, water content, density, volume solids,
and weight solids of paint, varnish, lacquer,
or related surface coatings.
1.2 Principle. Standard methods are used
to determine the volatile matter content,
water content, density, volume solids, and
weight solids of the paint, varnish, lacquer,
or related surface coatings.
2. Applicable Standard Methods
Use the apparatus, reagents, and proce-
dures specified in the standard methods
below:
2.1 ASTM D1475-60 (Reapproved 1980).
Standard Test Method for Density of Paint,
Varnish. Lacquer, and Related Products (in-
corporated by reference—see 5 60.17).
2.2 ASTM D2389-81, Standard Test
Method for Volatile Content of Coatings
(incorporated by reference—see 8 60.17).
2.3 ASTM D3792-79, Standard Test
Method for Water Content of Water-Reduc-
ible Paints by Direct Injection into a Gas
ChromatOKraph (incorporated by refer-
ence—see { 60.17).
2.4 ASTM D4017-81, Standard Test
Method for Water in Paints and Paint Ma-
terials by the Karl Fischer Tltratlon
Method (Incorporated by reference—see
J 60.17).
3. Procedure.
3.1 Volatile Matter Content. Use the pro-
cedure In ASTM D2369-81 (incorporated by
reference—see f 60.17) to determine the
volatile matter content (may include water)
of the coating. Record the following infor-
mation:
W,« Weight of dish and sample before heat-
ing, g.
Wt««Weight of dish and sample after heat-
Ing, g.
W.-Sample weight, g.
Run analyses in pairs (duplicate sets) for
each coating until the criterion In section
4.3 is met. Calculate the weight fraction of
the volatile matter (W.) for each analysis as
follows:
w.-
(Eq. 34-1)
Record the arithmetic average (W,).
3.2 Water Content. For waterborne
(water reducible) coatings only, determine
the weight fraction of water (w) using either
"Standard Content Method Test for Water
of Water-Reducible Paints by Direct Injec-
tion Into a Oas Chromatograph" or "Stand-
ard Test Method for Water in Paint and
Paint Materials by Karl Fischer Method."
(These two methods are Incorporated by
reference—see {60.17.) A waterborne coat-
Ing Is any coating which contains more than
5 percent water by weight In Its volatile
fraction. Run duplicate sets of determina-
tions until the criterion in section 4.3 Is met.
Record the arithmetic average (W.).
3.3 Coating Density. Determine the den-
sity (De, kg/liter) of the surface coating
using the procedure in ASTM D1475-60
(Reapproved 1980) (Incorporated by refer-
ence—see { 60.17).
Run duplicate sets of determinations for
each coating until the criterion in section
4.3 is met. Record the arithmetic average
(Dc>.
3.4 Solids Content. Determine the
volume fraction (V.) solids of the coating by
calculation using the manufacturer's formu-
lation.
4. Data, Validation Procedure
4.1 Summary- The variety of coatings
that may be subject to analysis makes it
necessary to verify the ability of the analyst
and the analytical procedures to obtain re-
producible results for the coatings tested.
This Is done by running duplicate analyses
on each sample tested and comparing re-
sults with the within-laboratory precision
statements for each parameter. Because of
the inherent increased Imprecision in the
determination of the VOC content of water-
borne coatings as the weight percent water
increases, measured parameters for water-
borne coatings are modified by the appro-
priate confidence limits based on between-
laboratory precision statements.
4.2 Analytical Precision Statements. The
within-laboratory and between-laboratory
precision statements are given below:
Wat* content Ww
Dwwtty, De
Within*
1— *>--—».» — .
wuQfWDry
Z9petWw
0.001 kg/KMr...
0**ftn-
woofvtofy
4.7 pet W..
7.5 pet W,
0.002 kg/ttw.
4.3 Sample Analysis Criteria. For W, and
W., run duplicate analyses until the differ-
ence between the two values in a set Is less
than or equal to the within-laboratory pre-
cision statement for that parameter. For D.
run duplicate analyses until each value in a
set deviates from the mean of the set by no
more than the within-laboratory precision
statement. If after several attempts it is
concluded that the ASTM procedures
634
C-3
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Chapter I—Environmental Protection Agency
Pt. 60, App. A, Math. 24A
cannot be used for the specific coating with
the established within-laboratory precision.
the Administrator will assume responsibility
for providing the necessary procedures for
revising the method or precision statements
upon written request to: Director. Emission
Standards and Engineering Division, (MD-
13) Office of Air Quality Planning and
Standards, U.S. Environmental Protection
Agency. Research Triangle Park, North
Carolina 27711.
4.4 Confidence Limit Calculations for
Waterbome Coatings. Based on the be-
tween-laboratory precision statements, cal-
culate the confidence limits for waterborne
coatings as follows:
To calculate the lower confidence limit,
subtract the appropriate between-laborato-
ry precision value from the measured mean
value for that parameter. To calculate the
upper confidence limit, add the appropirate
between-laboratory precision value to the
measured mean value for that parameter.
For W, and Dc, use the lower confidence
limits, and for Ww, use the upper confidence
limit. Because V. is calculated, there is no
adjustment for the parameter.
5. Calculations
5.1 Nonaqueous Volatile Matter.
5.1.1 Solvent-borne Coatings.
W.=W.
Eq. 24-2
Where:
W0=Weight fraction nonaqueous volatile
matter, g/g.
5.1.2 Waterborne Coatings.
We=W.-W. Eq. 24-3
5.2 Weight fraction solids.
W.=1-W, Eq. 24-4
Where: W.=Weight solids, g/g.
METHOD 24A—DETERMINATION OF VOLATILE
MATTER CONTENT AJTD DENSITY OF PRINT-
ING INKS AND RELATED COATINGS
1. Applicability and Principle.
1.1 Applicability. This method applies to
the determination of the volatile organic
compound (VOC) content and density of
solvent'bome (solvent reducible) printing
inks or related coatings.
1.2 Principle. Separate procedures are
used to determine the VOC weight fraction
and density of the coating and the density
of the solvent in the coating. The VOC
weight fraction is determined by measuring
the weight loss of a known sample quantity
which has been heated for a specified
length of time at a specified temperature.
The density of both the coating and solvent
are measured by a standard procedure.
Prom this information, the VOC volume
fraction is calculated.
2. Procedure.
2.1 Weight Fraction VOC.
2.1.1 Apparatus.
2.1.1.1 Weighing Dishes. Aluminum foil.
58 mm in diameter by 18 mm high, with a
flat bottom. There must be at least three
weighing dishes per sample.
2.1.1.2 Disposable syringe. 5 ml.
2.1.1.3 Analytical Balance. To measure to
within 0.1 mg.
2.1.1.4 Oven. Vacuum oven capable of
maintaining a temperature of 120±2'C and
an absolute pressure of 510 ±51 mm Hg for
4 hours. Alternatively, a farced draft oven
capable of maintaining a temperature of 120
±2°C for 24 hours.
2.1.1.5 Analysis. Shake or mix the sample
thoroughly to assure that all the solids are
completely suspended. Label and weigh to
the nearest 0.1 mg a weighing dish and
record this weight (M*).
Using a 5-ml syringe without a needle
remove a sample of the coating. Weigh the
syringe and sample to the nearest 0.1 mg
and record this weight (M.T,). Transfer 1 to
3 g of the sample to the tared weighing
dish. Reweigh the syringe and sample to the
nearest 0.1 mg and record this weight (!£,»).
Heat the weighing dish and sample in a
vacuum oven at an absolute pressure of 510
±51 mm Hg and a temperature of 120 ±2'C
for 4 hours. Alternatively, heat the weigh-
ing dish and sample in a forced draft oven
at a temperature of 120 ±2'C for 24 hours.
After the weighing dish has cooled, reweigh
it to the nearest 0.1 mg and record the
weight (Mil). Repeat this procedure for a
total of three determinations for each
sample.
2.2 Coating Density. Determine the den-
sity of the ink or related coating according
to the procedure outlined in ASTM D 1475-
60 (Reapproved 1980), which is incorporated
by reference. It is available from the Ameri-
can Society of Testing and Materials, 1916
Race Street, Philadelphia, Pennsylvania
19103. It is also available for inspection at
the Office of the Federal Register, Room
8401. 1100 L Street, NW.. Washington, D.C.
This incorporation by reference was ap-
proved by the Director of the Federal Regis-
ter on November 8, 1982. This material is in-
corporated as it exists on the date of ap-
proval and a notice of any change in these
materials will be published in the FEDERAL
REGISTER.
2.3 Solvent Density. Determine the den-
sity of the solvent according to the proce-
dure outlined in ASTM D 1475-60 (reap-
proved 1980). Make a total of three determi-
nations for each coating. Report the density
D0 as the arithmetic average of the three
determinations.
3. Calculations.
635
C-4
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Pt. 60, App. A, Meth. 25 Title 40—Protection of Environment
*
3.1 Weight Fraction VOC. Calculate the
weight fraction volatile organic content W.
using the following equation:
W.=
M.y,-McY,
(Eq.24A-l>
Report the weight fraction VOC W0 as the
arithmetic average of the three determina-
tions.
3.2 Volume Fraction VOC. Calculate the
volume fraction volatile organic content V,
using the following equation:
... _
Eq.24A-l
v W0DC
Eq. 24A-2
4. Bibliography.
4.1 Standard Test Method for Density of
Paint. Varnish, Lacquer, and Related Prod-
ucts. ASTM Designation D 1475-60 (Heap-
proved 1980).
4.2 Teleconversation. Wright, Chuck,
Inmont Corporation with Reich, R. A..
Radian Corporation. September 25, 1979.
Oravure Ink Analysis.
4.3 Teleconversation. Oppenhelmer,
Robert. Oravure Research Institute with
Burt. Rick. Radian Corporation, November
5,1979. Gravure Ink Analysis.
636
C-5
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TECHNICAL REPORT DATA .
(Please read Inurucnons CT the reverie before complennrl
1 REPORT NO. 2.
EPA 340/1-86-016
4 TITLE AND SUBTITLE
A Guideline for Surface Coating Calculations
7 AUTMOR(S)
PEI Associates, Inc.
9 PERFORMING ORGANIZATION NAME AND ADDRESS
PEI Associates, Inc.
1006 North Bowen Road
Suite 201
Arlington, Texas 76012
12. SPONSORING AGENCY NAME AND ADDRESS
U.S. Environmental Protection Agency
Stationary Source Compliance Division
401 M Street, S.W.
Washington, D.C. 20460
3. RECIPIENT'S ACCESSION NO.
5. REPORT DATE
February 1985
6. PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATION REPORT NO.
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
68-02-3963
13. TYPE OF REPORT AND PERIOD COVERED
14. SPONSOHING AGENCY CODE
15. SUPPLEMENTARY NOTES
16. ABSTRACT
The calr.ulatinn nf vnlatilp nraanir rnmnnunrl pmi<;<;inn<; frnm <;urfarp rnat-
ing operations to determine compliance is often a complicated task, sometimes
creating confusion with compliance authorities and sources alike. In an attempt
periodically issued guidance in this
the EPA Regional Offices. The most
Certifying Quantity of Volatile
Other Coatings," published December
confusion with
to minimize this confusion, EPA (OAQPS) has
area, generally in the form of memoranda to
recent document is entitled "Procedures for
Organic Compounds Emitted by Paint, Ink and
1984, EPA 450/3-84-019.
"A Guideline for Surface Coating Calculations" takes the above guidance
process one step further for surface coating operations. Guidance is provided
on how to compute existing and allowed emissions based on the above document as
well as previously issued Control Technique Guidelines for the individual cate-
gories. Example calculations are included for basic emission problems, com-
pliance determinations, equivalency determinations, application of transfer
efficiency, and calculations involving complex multiproduct plants. The approp-
riate data sheets, a list of various equations and notations, and graphs and
tables useful in making the above calculations are also included.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
COSATi I-itId/Cioup
Air Pollution
Surface Coating
VOC Data Sheets
Calculations
Compliance Determination
Control Strategy Evaluation
Air Pollution Control
Organic Chemicals
Coating Operations
Release Unlimited
19 SICuHl T » CL AiS
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