{"data":{"id":"us/40-cfr-1065.284","jurisdiction":"us","citation":"40 CFR 1065.284","heading":"Zirconium dioxide (ZrO2) air-fuel ratio and O2 analyzer.","body":"(a) Application. You may use a zirconia (ZrO2) analyzer to measure air-to-fuel ratio in raw exhaust for continuous sampling. You may use O2 measurements with intake air or fuel flow measurements to calculate exhaust flow rate according to § 1065.650.\n(b) Component requirements. We recommend that you use a ZrO2 analyzer that meets the specifications in § 1065.205. Note that your ZrO2-based system must meet the linearity verification in § 1065.307.","path":["Title 40—Protection of Environment","CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY","SUBCHAPTER U—AIR POLLUTION CONTROLS","PART 1065—ENGINE-TESTING PROCEDURES","Subpart C—Measurement Instruments"],"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":"60ef48cc0fa22f2b6284e52c5700f916901492fee943473a786481bf2edd2b6d","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-1065.280","next":"us/40-cfr-1065.290"},"notice":"GroundRules: Original legal text. Not legal advice."}