(a) The ambient air quality standards for total suspended particulate matter are:
- (1) 75 micrograms per cubic meter annual geometric mean; and
- (2) 150 micrograms per cubic meter maximum 24‑hour concentration not to be exceeded more than once per year.
- (b) Sampling and analysis shall be in accordance with procedures in 40 CFR Part 50, Appendix B or equivalent methods established pursuant to 40 CFR Part 53.
History Note: Authority G.S. 143‑215.3(a)(1); 143‑215.107(a)(3);
Eff. February 1, 1976;
Amended Eff. July 1, 1988; July 1, 1984; October 15, 1981;
Readopted Eff. November 1, 2020.