VOC Content = (Ws - Ww - Wec)/(Vm - Vw - Vec)
where:
VOC content = grams of VOC per liter of coating
Ws = weight of volatiles, in grams
Ww = weight of water, in grams
Wec = weight of exempt compounds, in grams
Vm = volume of coating, in liters
Vw = volume of water, in liters
Vec = volume of exempt compounds, in liters
VOC Content (ls) = (Ws - Ww - Wec)/(Vm)
where:
VOC content (ls) = the VOC content of a low solids coating in grams per liter of coating
Ws = weight of volatiles, in grams
Ww = weight of water, in grams
Wec = weight of exempt compounds, in grams
Vm = volume of coating, in liters
To determine the physical properties of a coating in order to perform the calculations in subdivision (b) of this section, the reference method for VOC content is found at 40 CFR part 60, appendix A, method 24 (2000) (see Table 1, section 200.9 of this Title), except as provided in subdivisions (d) and (e) of this section. An alternate method to determine the VOC content of coatings is South Coast Air Quality Management District Method 304-91 (Revised February 1996) (see Table 1, section 200.9 of this Title). The exempt compounds content shall be determined by methods referenced in ASTM D3960-05 (2013), South Coast Air Quality Management District Method 303-91 (Revised August 1996), or Bay Area Air Quality Management District (BAAQMD) Method 41 (Revised 2005), as applicable (see Table 1, section 200.9 of this Title). To determine the VOC content of a coating, the manufacturer may use 40 CFR part 60, appendix A, method 24 (see Table 1, section 200.9 of this Title), or an alternative method, as provided in subdivision (c) of this section, manufacturer's formulation data, or any other reasonable means for predicting that the coating has been formulated as intended (e.g., quality assurance checks, recordkeeping). However, if there are any inconsistencies between the results of a 40 CFR part 60, appendix A, method 24 (see Table 1, section 200.9 of this Title) test and any other methods for determining VOC content, the 40 CFR part 60, appendix A, method 24 (see Table 1, section 200.9 of this Title) results will govern, except when an alternative method is approved as specified in subdivision (d) of this section. The director, Division of Air Resources, Department of Environmental Conservation may require the manufacturer to conduct a 40 CFR part 60, appendix A, method 24 (see Table 1, section 200.9 of this Title) analysis to determine the VOC content.
Other test methods demonstrated to provide results that are acceptable for purposes of determining compliance with subdivision (c) of this section, after review and approval in writing by the director, Division of Air Resources, Department of Environmental Conservation and the EPA, may also be used.
Analysis of methacrylate multicomponent coatings used as traffic marking coatings shall be conducted according to a modification of 40 CFR part 60, appendix A, method 24 found at 40 CFR part 59, subpart D, appendix A (see Table 1, section 200.9 of this Title). This method has not been approved for methacrylate multicomponent coatings used for other purposes than as traffic marking coatings or for other classes of multicomponent coatings.
N.Y. Comp. Codes R. & Regs. Tit. 6 § 205.6