40 CFR §60.3038

1. (a)For each OSWI unit with a capacity greater than 10 tons per day, you must install, calibrate, maintain, and operate continuous emission monitoring systems for carbon monoxide and for oxygen. You must monitor the oxygen concentration at each location where you monitor carbon monoxide.
2. (b)You must install, evaluate, and operate each continuous emission monitoring system according to the “Monitoring Requirements” in § 60.13.