40 Protection of Environment 2 1997-07-01 1997-07-01 false Reference conditions. 50.3 Section 50.3 AIR PROGRAMS NATIONAL PRIMARY AND SECONDARY AMBIENT AIR QUALITY STANDARDS
§ 50.3 Reference conditions.

All measurements of air quality are corrected to a reference temperature of 25 °C. and to a reference pressure of 760 millimeters of mercury (1,013.2 millibars).