Illinois Administrative Code
Title 35 - ENVIRONMENTAL PROTECTION
Part 243 - AIR QUALITY STANDARDS
Subpart B - STANDARDS AND MEASUREMENT METHODS
Section 243.120 - PM10 and PM2.5

1) The level of the 1987 primary and secondary 24-hour NAAQS for PM10 is 150 µg/m3, 24-hour average concentration. The 1987 primary and secondary NAAQS for PM10 is attained when the expected number of days per calendar year with a 24-hour average concentration above 150 µg/m3, as determined in accordance with appendix K to 40 CFR 50, incorporated by reference in Section 243.108, is equal to or less than one.

2) This subsection (a)(2) corresponds with 40 CFR 50.6(b), a provision marked "reserved" by USEPA. This statement maintains structural consistency with the corresponding federal regulation.

3) For the purpose of determining attainment of the 1987 primary and secondary 24-hour NAAQS for PM10, particulate matter must be measured in the ambient air as PM10 by a method that fulfills either of the following requirements:

1) The 1997 secondary annual average NAAQS for PM2.5 is 15.0 µg/m3, annual arithmetic mean concentration, and the 1997 primary and secondary 24-hour NAAQS for PM2.5 is 65 µg/m3, 24-hour average concentration, measured in the ambient air as PM2.5 by a method that fulfills either of the following requirements:

2) The 1997 secondary annual average NAAQS for PM2.5 is met when the annual arithmetic mean concentration, as determined in accordance with appendix N of 40 CFR 50, incorporated by reference in Section 243.108, is less than or equal to 15.0 µg/m3.

3) The 1997 primary and secondary 24-hour NAAQS for PM2.5 is met when the 98th percentile 24-hour concentration, as determined in accordance with appendix N of 40 CFR 50, incorporated by reference in Section 243.108, is less than or equal to 65 µg/m3.

BOARD NOTE: This subsection (b) is derived from 40 CFR 50.7.

1) The 2006 secondary annual average NAAQS for PM2.5 is 15.0 µg/m3, annual arithmetic mean concentration, and the 2006 primary and secondary 24-hour NAAQS for PM2.5 is 35 µg/m3, 24-hour average concentration, measured in the ambient air as PM2.5 by a method that fulfills either of the following requirements:

2) The 2006 secondary annual average NAAQS for PM2.5 is met when the annual arithmetic mean concentration, as determined in accordance with appendix N of 40 CFR 50, incorporated by reference in Section 243.108, is less than or equal to 15.0 µg/m3.

3) The 2006 primary and secondary 24-hour NAAQS for PM2.5 is met when the 98th percentile 24-hour concentration, as determined in accordance with appendix N of 40 CFR 50, incorporated by reference in Section 243.108, is less than or equal to 35 µg/m3.

BOARD NOTE: This subsection (c) is derived from 40 CFR 50.13.

1) The 2012 primary annual average NAAQS for PM2.5 is 12.0 µg/m3 annual arithmetic mean concentration, and the 2012 primary 24-hour NAAQS for PM2.5 is 35 µg/m3 24-hour average concentration, measured in the ambient air as PM2.5 by a method that fulfills either of the following requirements:

2) The 2012 primary annual NAAQS for PM2.5 is met when the annual arithmetic mean concentration, as determined in accordance with appendix N of 40 CFR 50, incorporated by reference in Section 243.108, is less than or equal to 12.0 µg/m3.

3) The 2012 primary 24-hour NAAQS for PM2.5 is met when the 98th percentile 24-hour concentration, as determined in accordance with appendix N of 40 CFR 50, incorporated by reference in Section 243.108, is less than or equal to 35 µg/m3.