{"data":{"id":"us/40-cfr-63.8590","jurisdiction":"us","citation":"40 CFR 63.8590","heading":"When must I conduct subsequent performance tests?","body":"(a) For each affected source that is subject to the emission limits specified in Table 1 to this subpart, you must conduct a performance test before renewing your 40 CFR part 70 operating permit or at least every 5 years following the initial performance test.\n(b) You must conduct a performance test when you want to change the parameter value for any operating limit specified in your OM\u0026M plan.","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 KKKKK—National Emission Standards for Hazardous Air Pollutants for Clay Ceramics Manufacturing"],"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":"5f60271ec5786b5837aa42b0a30a2cb9732da3250f586f249e73ea7d825d4038","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-63.8585","next":"us/40-cfr-63.8595"},"notice":"GroundRules: Original legal text. Not legal advice."}