# 40 CFR § 1065.675 - CLD quench verification calculations.

Perform CLD quench-check calculations as follows:

(a) Perform a CLD analyzer quench verification test as described in § 1065.370.

(b) Estimate the maximum expected mole fraction of water during emission testing, xH2Oexp. Make this estimate where the humidified NO span gas was introduced in § 1065.370(e)(6). When estimating the maximum expected mole fraction of water, consider the maximum expected water content in intake air, fuel combustion products, and dilution air (if applicable). If you introduced the humidified NO span gas into the sample system upstream of a sample dryer during the verification test, you need not estimate the maximum expected mole fraction of water and you must set xH2Oexp equal to xH2Omeas.

(c) Estimate the maximum expected CO2 concentration during emission testing, xCO2exp. Make this estimate at the sample system location where the blended NO and CO2 span gases are introduced according to § 1065.370(d)(10). When estimating the maximum expected CO2 concentration, consider the maximum expected CO2 content in fuel combustion products and dilution air.

(d) Calculate quench as follows: