§ 53.50 General provisions.

(a) A candidate method for PM _2.5 or PM _10–2.5 described in an application for a FRM or FEM determination submitted under § 53.4 shall be determined by the EPA to be a FRM or a Class I, II, or III FEM on the basis of the definitions for such methods given in § 53.1. This subpart sets forth the specific tests that must be carried out and the test results, evidence, documentation, and other materials that must be provided to EPA to demonstrate that a PM _2.5 or PM _10–2.5 sampler associated with a candidate reference method or Class I or Class II equivalent method meets all design and performance specifications set forth in appendix L or O, respectively, of part 50 of this chapter as well as additional requirements specified in this subpart E. Some or all of these tests may also be applicable to a candidate Class III equivalent method or analyzer, as may be determined under § 53.3(b)(3).

(b) PM2.5methods—(1) Reference method. A sampler associated with a candidate reference method for PM _2.5 shall be subject to the provisions, specifications, and test procedures prescribed in §§ 53.51 through 53.58.

(2) Class I method. A sampler associated with a candidate Class I equivalent method for PM _2.5 shall be subject to the provisions, specifications, and test procedures prescribed in all sections of this subpart.

(3) Class II method. A sampler associated with a candidate Class II equivalent method for PM _2.5 shall be subject to the provisions, specifications, and test procedures prescribed in all applicable sections of this subpart, as specified in subpart F of this part or as specified in § 53.3(a)(3).