SUBTITLE B: AIR POLLUTION
CHAPTER I: POLLUTION CONTROL BOARD
SUBCHAPTER l: AIR QUALITY STANDARDS AND EPISODES
PART 243 AIR QUALITY STANDARDS
SECTION 243.120 PM10 AND PM2.5
Section 243.120 PM10 and PM2.5
a) Standards. The primary and secondary ambient air quality standards for PM10 are a maximum 24-hour average concentration of 150 µg/m³. The standards are attained when the expected number of days per calendar year with a 24-hour average concentration above 150 µg/m³ is equal to or less than one, as measured and determined in accordance with subsection (b).
b) Measurement Method. For determining conformance with the PM10 ambient air quality standards, PM10 shall be measured by the method described in 40 CFR 50, appendix J or an equivalent method designated pursuant to 40 CFR 53 (incorporated by reference in Section 243.108). The standards are attained when the expected number of days per calendar year with a 24-hour average concentration above 150 µg/m³ is equal to or less than one, as determined in accordance with 40 CFR 50, appendix K (incorporated by reference in Section 243.108).
c) Standards. The primary and secondary ambient air quality standards for PM2.5 are:
1) An annual arithmetic mean concentration of 15.0 µg/m³ and as measured and determined in conformance with subsection (d).
2) A maximum 24-hour concentration of 35µg/m³, at the 98th percentile value, and as measured and determined in conformance with subsection (d).
d) Measurement Method for PM2.5. For determining conformance with the PM2.5 ambient air quality standards, PM2.5 shall be measured by the method described in 40 CFR 50, appendix L or an equivalent method designated pursuant to 40 CFR 53 (incorporated by reference in Section 243.108). Compliance with the standards is determined using the methods and procedures described in 40 CFR 50, appendix N (incorporated by reference in Section 243.108).
1) The annual primary and secondary PM2.5 standards are met when the annual arithmetic mean concentration, as determined in accordance with 40 CFR 50, appendix N, is less than or equal to 15.0 µg/m3.
2) The 24-hour primary and secondary PM2.5 standards are met when the 98th percentile 24-hour concentration, as determined in accordance with 40 CFR 50, appendix N, is less than or equal to 35 µg/m3.
(Source: Amended at 35 Ill. Reg. 18857, effective October 25, 2011)