(a) Application. You may use a zirconia (ZrO2) analyzer to measure air-to-fuel ratio in raw exhaust for continuous sampling. You may use O2 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 ZrO2 analyzer that meets the specifications in Table 1 of §1065.205. Note that your ZrO2-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]