40 CFR §63.5121

1. (a)Except as provided in paragraph (b) of this section, for any coil coating line for which you use an add-on control device, unless you use a solvent recovery system and conduct a liquid-liquid material balance according to § 63.5170(e)(1), you must meet the applicable operating limits specified in Table 1 to this subpart. You must establish the operating limits during performance tests according to the requirements in § 63.5160(d)(3) and Table 1 to § 63.5160. You must meet the operating limits established during the most recent performance test required in § 63.5160 at all times after you establish them.
2. (b)If you use an add-on control device other than those listed in Table 1 to this subpart, or wish to monitor an alternative parameter and comply with a different operating limit, you must apply to the Administrator for approval of alternative monitoring under § 63.8(f).