{"data":{"id":"us/40-cfr-63.9920","jurisdiction":"us","citation":"40 CFR 63.9920","heading":"What are my continuous monitoring requirements?","body":"For each wet scrubber subject to the operating limits for pressure drop and scrubber water flow rates in § 63.9890(b), you must at all times monitor the hourly average pressure drop and liquid flow rate using a CPMS according to the requirements in § 63.9921(a).","path":["Title 40—Protection of Environment","CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY","SUBCHAPTER C—AIR PROGRAMS","PART 63—NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS FOR SOURCE CATEGORIES","Subpart TTTTT—National Emissions Standards for Hazardous Air Pollutants for Primary Magnesium Refining"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-40.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:04Z","sha256":"831b86ee5dc4d4d0802823ef2904ea40dce8c0b17ec6e3e23c0276ba5591e34e","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-63.9918","next":"us/40-cfr-63.9921"},"notice":"GroundRules: Original legal text. Not legal advice."}