Zirconium dioxide (ZrO 2 ) air-fuel ratio and O 2 analyzer.

(a) Application. You may use a zirconia (ZrO 2 ) analyzer to measure air-to-fuel ratio in raw exhaust for continuous sampling. You may use O 2 measurements with intake air or fuel flow measurements to calculate exhaust flow rate according to § 1065.650. (b) Component requirements. We recommend that you use a ZrO 2 analyzer that meets the specifications in § 1065.205. Note that your ZrO 2 -based system must meet the linearity verification in § 1065.307. [70 FR 40516, July 13, 2005, as amended at 76 FR 57443, Sept. 15, 2011; 79 FR 23762, Apr. 28, 2014; 89 FR 29797, Apr. 22, 2024]