(a) Application. You may use a paramagnetic detection (PMD) or magnetopneumatic detection (MPD) analyzer to measure O2 concentration in raw or diluted exhaust for batch or continuous sampling. You may use good engineering judgment to develop calculations that use O2 measurements with a chemical balance of fuel, DEF, intake air, and exhaust to calculate exhaust flow rate.

(b) Component requirements. We recommend that you use a PMD or MPD analyzer that meets the specifications in § 1065.205. Note that it must meet the linearity verification in § 1065.307.

[73 FR 37300, June 30, 2008, as amended at 76 FR 57443, Sept. 15, 2011;79 FR 23762, Apr. 28, 2014; 86 FR 34536, June 29, 2021; 89 FR 29797, Apr. 22, 2024]