StacksVerified U.S. federal law reference

40 CFR Part 62, Table 2 — Operating Limits for Wet Scrubbers

Verified against eCFR.gov as of June 20, 2026View official text on eCFR.gov ↗
For these operating parametersYou must establish these operating limitsAnd monitor using these minimum frequencies
Data measurementData recordingAveraging time
Charge rateMaximum charge rateContinuous | Every hour | 1. Daily (batch units)2. 3-hour rolling (continuous and intermittent units) a
Pressure drop across the wet scrubber or amperage to wet scrubberMinimum pressure drop or amperageContinuous | Every 15 minutes | 3-hour rolling a
Scrubber liquor flow rateMinimum flow rateContinuous | Every 15 minutes | 3-hour rolling a
Scrubber liquor pHMinimum pHContinuous | Every 15 minutes | 3-hour rolling a

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