--- kind: "section" citation: "40 C.F.R. § 63.3966" title: "40" number: "63.3966" heading: "How do I determine the add-on control device emission destruction or removal efficiency?" url: "https://uscodex.org/cfr/40/63.3966" --- # §63.3966. How do I determine the add-on control device emission destruction or removal efficiency? You must use the procedures and test methods in this section to determine the add-on control device emission destruction or removal efficiency as part of the performance test required by [§ 63.3960](/cfr/40/63.3960.md). For each performance test, you must conduct three test runs as specified in [§ 63.7(e)(3)](/cfr/40/63.7.md?p=e-3) and each test run must last at least 1 hour. If the source is a magnet wire coating machine, you may use the procedures in [section 3.0](/cfr/40/3.0.md) of appendix A to this subpart as an alternative. - (a) For all types of add-on control devices, use the test methods specified in [paragraphs (a)(1) through (5)](#a-1..a-5) of this section. - (1) Use Method 1 or 1A of appendix A to [40 CFR part 60](/cfr/40/part60.md), as appropriate, to select sampling sites and velocity traverse points. - (2) Use Method 2, 2A, 2C, 2D, 2F, or 2G of appendix A to [40 CFR part 60](/cfr/40/part60.md), as appropriate, to measure gas volumetric flow rate. - (3) Use Method 3, 3A, or 3B of appendix A to [40 CFR part 60](/cfr/40/part60.md), as appropriate, for gas analysis to determine dry molecular weight. - (4) **Use Method 4 of appendix A to 40 CFR part 60, to determine stack gas moisture.** - (5) Methods for determining gas volumetric flow rate, dry molecular weight, and stack gas moisture must be performed, as applicable, during each test run. - (b) Measure total gaseous organic mass emissions as carbon at the inlet and outlet of the add-on control device simultaneously, using either EPA Method 25 or 25A of appendix A-7 to [40 CFR part 60](/cfr/40/part60.md). - (1) Use EPA Method 25 of appendix A-7 to [40 CFR part 60](/cfr/40/part60.md) if the add-on control device is an oxidizer and you expect the total gaseous organic concentration as carbon to be more than 50 parts per million (ppm) at the control device outlet. - (2) Use EPA Method 25A of appendix A-7 to [40 CFR part 60](/cfr/40/part60.md) if the add-on control device is an oxidizer and you expect the total gaseous organic concentration as carbon to be 50 ppm or less at the control device outlet. - (3) **Use EPA Method 25A of appendix A-7 to 40 CFR part 60 if the add-on control device is not an oxidizer.** - (4) You may use EPA Method 18 of appendix A-6 to [40 CFR part 60](/cfr/40/part60.md) to subtract methane emissions from measured total gaseous organic mass emissions as carbon. - (c) If two or more add-on control devices are used for the same emission stream, then you must measure emissions at the outlet to the atmosphere of each device. For example, if one add-on control device is a concentrator with an outlet to the atmosphere for the high-volume dilute stream that has been treated by the concentrator, and a second add-on control device is an oxidizer with an outlet to the atmosphere for the low-volume concentrated stream that is treated with the oxidizer, you must measure emissions at the outlet of the oxidizer and the high volume dilute stream outlet of the concentrator. - (d) For each test run, determine the total gaseous organic emissions mass flow rates for the inlet and the outlet of the add-on control device, using Equation 1 of this section. If there is more than one inlet or outlet to the add-on control device, you must calculate the total gaseous organic mass flow rate using Equation 1 of this section for each inlet and each outlet and then total all of the inlet emissions and total all of the outlet emissions: - (e) For each test run, determine the add-on control device organic emissions destruction or removal efficiency, using Equation 2 of this section: - (f) Determine the emission destruction or removal efficiency of the add-on control device as the average of the efficiencies determined in the three test runs and calculated in Equation 2 of this section. ## Notes ### Amendments [69 FR 157, Jan. 2, 2004, as amended at 85 FR 41143, July 8, 2020] ### Source Source: 69 FR 157, Jan. 2, 2004, unless otherwise noted. ### Authority Authority: 42 U.S.C. 7401 et seq. ### Source Source: 57 FR 61992, Dec. 29, 1992, unless otherwise noted. ### Amendments [69 FR 157, Jan. 2, 2004, as amended at 85 FR 41143, July 8, 2020]