(a) Where continuous emission monitoring systems are required, obtain 1-hour arithmetic averages. Except for CEMS data during startup and shutdown, as defined in this subpart, the 1-hour arithmetic averages for carbon monoxide must be expressed in parts per million by dry volume corrected to 7 percent oxygen. The CEMS data during startup and shutdown are not corrected to 7 percent oxygen and are measured at stack oxygen content. Use the 1-hour averages of oxygen data from your CEMS to determine the actual oxygen level and to calculate emissions at 7 percent oxygen. Use Equation 2 in § 60.2975 to calculate the 12-hour rolling averages from the 1-hour arithmetic averages.

(b) Obtain at least two data points per hour in order to calculate a valid 1-hour arithmetic average. Section 60.13(e)(2) requires your continuous emission monitoring systems to complete at least one cycle of operation (sampling, analyzing, and data recording) for each 15-minute period.

(c) Obtain valid 1-hour averages for at least 75 percent of the operating hours per day for at least 90 percent of the operating days per calendar quarter. An operating day is any day the unit combusts any municipal or institutional solid waste.

(d) If you do not obtain the minimum data required in paragraphs (a) through (c) of this section, you have deviated from the data collection requirement regardless of the emission level monitored.

(e) If you do not obtain the minimum data required in paragraphs (a) through (c) of this section, you must still use all valid data from the continuous emission monitoring systems in calculating emission concentrations.

(f) If continuous emission monitoring systems are temporarily unavailable to meet the data collection requirements, refer to table 3 to this subpart. It shows alternate methods for collecting data when systems malfunction or when repairs, calibration checks, or zero and span checks keep you from collecting the minimum amount of data. Failure to collect required data is a deviation of the monitoring requirements.