Section R18-2-202. Sulfur Oxides (Sulfur Dioxide)

A.      The primary ambient air quality standards for sulfur oxides, measured as sulfur dioxide, are:

1.        0.03 parts per million (ppm) (80 µg/m3) -- annual arith-

metic mean.

2.        0.14 parts per million (ppm) (365 µg/m3) – maximum 24- hour concentration not to be exceeded more than once per calendar year.

3.        75 parts per billion (ppb) – maximum one-hour concen- tration. The one-hour primary standard is met at an ambi- ent air quality monitoring site when the three-year average of the annual 99th percentile of the daily maxi- mum one-hour average concentrations is less than or equal to 75 parts per billion, as determined according to 40 CFR 50, Appendix T.

B.       The secondary ambient air quality standard for sulfur oxides, measured as sulfur dioxide, is 0.5 parts per million (ppm) (1300 µg/m3) -- maximum three-hour concentration not to be

exceeded more than once per year.

C.      The level of the standards shall be measured by a reference method based on 40 CFR 50, Appendix A or A-1, or by a Fed- eral Equivalent Method designated according to 40 CFR 53.

D.      The standards in subsections (A)(1) and (2) shall apply:

1.        In an area designated nonattainment for a standard in sub- section (A)(1) or (2) as of August 23, 2011, and areas not meeting a state implementation plan call for a standard in subsection (A)(1) or (2), until the state submits pursuant to section 191 of the Act, and the Administrator approves, a state implementation plan providing for attainment the standard in subsection (A)(3) in that area.

2.        In areas other than those identified in subsection (D)(1), until the effective date of the designation of that area, pur- suant to section 107 of the act, for the standard in subsec- tion (A)(3).

Historical Note

Amended effective December 22, 1976 (Supp. 76-5). Former Section R9-3-202 repealed, new Section R9-3- 202 adopted effective May 14, 1979 (Supp. 79-1).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 subsection (B) effective May 28, 1982 (Supp. 82-3). Amended by deleting subsections (C) through (E) effective September 22, 1983 (Supp. 83-5). Former Sec- tion R9-3-202 renumbered without change as Section R18-2-202 (Supp. 87-3). 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, effec- tive August 7, 2012 (Supp. 12-2).