Code of Federal Regulations > Title 40 > Chapter I > Part 60 > Subpart DDDD > Appendix - Table 3 to Subpart DDDD of Part 60—Model Rule

Regulations last checked for updates: Feb 22, 2025

Title 40 - Protection of Environment last revised: Nov 22, 2025

Appendix - Table 3 to Subpart DDDD of Part 60—Model Rule—Operating Limits for Wet Scrubbers

For these operating parameters	You must establish these operating limits	And monitor using these minimum frequencies
For these operating parameters	You must establish these operating limits	Data measurement	Data recording	Averaging time
Charge rate	Maximum charge rate	Continuous	Every hour	Daily (batch units). 3-hour rolling (continuous and intermittent units). ¹
Pressure drop across the wet scrubber or amperage to wet scrubber	Minimum pressure drop or amperage	Continuous	Every 15 minutes	3-hour rolling. ¹
Scrubber liquor flow rate	Minimum flow rate	Continuous	Every 15 minutes	3-hour rolling. ¹
Scrubber liquor pH	Minimum pH	Continuous	Every 15 minutes	3-hour rolling. ¹

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

authority: 42 U.S.C. 7401

source: 36 FR 24877, Dec. 23, 1971, unless otherwise noted.