Section 60.456 - Test methods and procedures(a) The reference methods in appendix A to this part, except as provided under § 60.8(b) , shall be used to determine compliance with § 60.452 as follows: (1) Method 24 or formulation data supplied by the coating manufacturer to determine the VOC content of a coating. In the event of dispute, Method 24 shall be the reference method. For determining compliance only, results of Method 24 analyses of waterborne coatings shall be adjusted as described in Section 12.6 of Method 24. Procedures to determine VOC emissions are provided in § 60.453 .(2) Method 25 for the measurement of the VOC concentration in the gas stream vent.(3) Method 1 for sample and velocity traverses.(4) Method 2 for velocity and volumetric flow rate.(5) Method 3 for gas analysis.(6) Method 4 for stack gas moisture.(b) For Method 24, the coating sample must be a 1-liter sample taken into a 1-liter container at a point where the sample will be representative of the coating material.(c) For Method 25, the sample time for each of three runs is to be at least 60 minutes and the minimum sample volume is to be at least 0.003 dscm (0.1 dscf) except that shorter sampling times or smaller volumes, when necessitated by process variables or other factors, may be approved by the Administrator.(d) The Administrator will approve sampling of representative stacks on a case-by-case basis if the owner or operator can demonstrate to the satisfaction of the Administrator that the testing of representative stacks would yield results comparable to those that would be obtained by testing all stacks.47 FR 47785, Oct. 27, 1982, as amended at 65 FR 61761 , Oct. 17, 2000