StacksVerified U.S. federal law reference

40 CFR Part 60, Table 3 — Model Rule—Operating Limits for Wet Scrubbers

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
For these operatingparametersYou must establish these operating limitsAnd monitor using these minimum frequencies
DatameasurementDatarecordingAveraging time
Charge rateMaximum charge rateContinuous | Every hour | Daily (batch units). 3-hour rolling (continuous and intermittent units).1
Pressure drop across the wet scrubber or amperage to wet scrubberMinimum pressure drop or amperageContinuous | Every 15 minutes | 3-hour rolling.1
Scrubber liquor flow rateMinimum flow rateContinuous | Every 15 minutes | 3-hour rolling.1
Scrubber liquor pHMinimum pHContinuous | Every 15 minutes | 3-hour rolling.1

1 Calculated each hour as the average of the previous 3 operating hours.