GroundRules
40 CFR Table C-1 to Subpart C of Part 53: Table C-1 to Subpart C of Part 53—Test Concentration Ranges, Number of Measurements Required, and Maximum Discrepancy Specifications
Where this section sits in the code
- Title 40—Protection of Environment
- CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY
- SUBCHAPTER C—AIR PROGRAMS
- PART 53—AMBIENT AIR MONITORING REFERENCE AND EQUIVALENT METHODS
- Subpart C—Procedures for Determining Comparability Between Candidate Methods and Reference Methods
Pollutant Concentration range, parts per million (ppm) Simultaneous measurements required Maximum discrepancy specification, parts per million
1-hour 24-hour
First set Second set First set Second set
Ozone Low 0.06 to 0.10 5 6 0.02
Med. 0.15 to 0.25 5 6 0.03
High 0.35 to 0.46 4 6 0.04
Total 14 18
Carbon monoxide Low 7 to 11 5 6 1.5
Med. 20 to 30 5 6 2.0
High 25 to 45 4 6 3.0
Total 14 18
Sulfur dioxide Low 0.02 to 0.05 5 6 3 3 0.02
Med. 0.10 to 0.15 5 6 2 3 0.03
High 0.30 to 0.50 4 6 2 2 0.04
Total 14 18 7 8
Nitrogen dioxide Low 0.02 to 0.08 3 3 0.02
Med. 0.10 to 0.20 2 2 0.02
High 0.25 2 2 0.03
Total 7 8
Collected 2026-08-27T02:26:04Z. Source file · JSON