Code of Federal Regulations > Title 40 > Chapter I > Part 53 > Subpart C > Appendix - Table C-5 to Subpart C of Part 53—Summary of Comparability Field Testing Campaign Site and Seasonal Requirements for Class II and III FEMs for PM 10-2.5 and PM 2.5

Regulations last checked for updates: Apr 17, 2025

Title 40 - Protection of Environment last revised: Feb 17, 2028

Appendix - Table C-5 to Subpart C of Part 53—Summary of Comparability Field Testing Campaign Site and Seasonal Requirements for Class II and III FEMs for PM 10-2.5 and PM 2.5

Candidate method	Test site	A	B	C	D
PM 2.5	Test site location area	Los Angeles basin or California Central Valley	Western city such as Denver, Salt Lake City, or Albuquerque	Midwestern city	Northeastern or mid-Atlantic city.
	Test site characteristics	Relatively high PM 2.5, nitrates, and semi-volatile organic pollutants	Cold weather, higher elevation, winds, and dust	Substantial temperature variation, high nitrates, wintertime conditions	High sulfate and high relative humidity.
	Class III Field test campaigns (Total: 5)	Winter and summer	Winter only	Winter only	Summer only.
	Class II Field test campaigns (Total: 2)	Site A or B, any season		Site C or D, any season.
PM 10-2.5	Test site location area	Los Angeles basin or California Central Valley	Western city such as Las Vegas or Phoenix	Midwestern city	Large city east of the Mississippi River.
	Test site characteristics	Relatively high PM 2.5, nitrates, and semi-volatile organic pollutants	High PM 10-2.5 to PM 2.5 ratio, windblown dust	Substantial temperature variation, high nitrates, wintertime conditions	High sulfate and high relative humidity.
	Class III Field test campaigns (Total: 5)	Winter and summer	Winter only	Winter only	Summer only.
	Class II Field test campaigns (Total: 2)	Site A or B, any season		Site C or D, any season.

authority: Sec. 301(a) of the Clean Air Act (42 U.S.C. sec. 1857g(a)), as amended by sec. 15(c)(2) of Pub. L. 91-604, 84 Stat. 1713, unless otherwise noted

source: 40 FR 7049, Feb. 18, 1975, unless otherwise noted.