(a) Application. You may use a gas chromatograph with a flame ionization detector (GC-FID) to measure CH4 concentrations of diluted exhaust for batch sampling. While you may also use a nonmethane cutter to measure CH4, as described in Sec. 1065.265, use a reference procedure based on a gas chromatograph for comparison with any proposed alternate measurement procedure under Sec. 1065.10.
(b) Component requirements. We recommend that you use a GC-FID that meets the specifications in Table 1 of Sec. 1065.205 and that the measurement be done according to SAE J1151 (incorporated by reference in Sec. 1065.1010). The GC-FID must meet the linearity verification in Sec. 1065.307. [76 FR 57442, Sept. 15, 2011, as amended at 79 FR 23761, Apr. 28, 2014]