Section R18-2-203. Ozone: One-hour Standard and Eight-hour Aver- age Standard

A.      One-hour standard. Until June 15, 2005:

1.        The one-hour ambient air quality standard for ozone is

0.12 ppm (235 micrograms per cubic meter).

2.        The one-hour secondary ambient air quality standard for ozone is 0.12 ppm (235 micrograms per cubic meter).

3.        The one-hour standards are attained when the expected number of days per calendar year with maximum hourly average concentrations above 0.12 ppm (235 micrograms per cubic meter) is less than or equal to 1, determined by 40 CFR 50, Appendix H.

B.       Eight-hour averaged standard.

1.        The eight-hour average primary ambient air quality stan- dard for ozone is 0.075 ppm.

2.        The eight-hour average secondary ambient air quality standard for ozone is 0.075 ppm.

3.        To determine attainment of the primary and secondary standards, a person shall measure ozone in the ambient air by:

Department of Environmental Quality – Air Pollution Control

a.         A reference method based on 40 CFR 50, Appendix D, and designated according to 40 CFR 53; or

b.        An equivalent method designated according to 40 CFR 53.

4.        Eight-hour average primary and secondary ambient air quality standards for ozone are met at an ambient air quality monitoring site when the three-year average of the annual fourth highest daily maximum eight-hour average ozone concentration is less than or equal to 0.075 ppm, determined according to 40 CFR 50, Appendix P.

Historical Note

Amended effective December 22, 1976 (Supp. 76-5). Former Section R9-3-204 repealed, new Section R9-3- 204 adopted effective May 14, 1979 (Supp. 79-1).

Amended effective October 2, 1979 (Supp. 79-5).

Amended effective August 29, 1980 (Supp. 80-4).

Amended by deleting subsections (B) through (D) effec- tive September 22, 1983 (Supp. 83-5). Former Section R9-3-204 renumbered without change as Section R18-2- 204 (Supp. 87-3). Section R18-2-103 renumbered from R18-2-204 and amended effective September 26, 1990 (Supp. 90-3). Amended by final rulemaking at 11 A.A.R. 3305, effective October 3, 2005 (Supp. 05-3). Amended by final rulemaking at 18 A.A.R. 1542, effective August 7, 2012 (Supp. 12-2).