DEPARTMENT OF ENVIRONMENTAL QUALITY

DIVISION 202

AMBIENT AIR QUALITY STANDARDS AND PSD INCREMENTS

340-202-0060

Suspended Particulate Matter

Concentrations of the fraction of suspended particulate that is equal to or less than ten microns in aerodynamic diameter in ambient air as measured by an approved method must not exceed:

(1) 150 micrograms of PM10 per cubic meter of air as a 24-hour average concentration for any calendar day. This standard is attained when the expected number of days per calendar year with a 24-hour average concentration above 150 micrograms per cubic meter as determined in accordance with Appendix K of 40 CFR 50 is equal to or less than one at any site.

Concentrations of the fraction of suspended particulate that is equal to or less than 2.5 microns in aerodynamic diameter in ambient air as measured by an approved method must not exceed:

(2) 35 micrograms of PM2.5 per cubic meter of air as a 3-year average of annual 98th percentile 24-hour average values recorded at each monitoring site. This standard is attained when the 3-year average of annual 98th percentile 24-hour average concentrations is equal to or less than 35 micrograms per cubic meter as determined in accordance with Appendix N of 40 CFR 50.

(3) 15 micrograms of PM2.5 per cubic meter of air as a 3-year average of the annual arithmetic mean. This standard is attained when the annual arithmetic mean concentration is equal to or less than 15 micrograms per cubic meter as determined in accordance with Appendix N of 40 CFR 50.

NOTE: This rule is included in the State of Oregon Clean Air Act Implementation Plan as adopted by the Environmental Quality Commission under OAR 340-200-0040.

Stat. Auth.: ORS 468 & 468A
Stats. Implemented: ORS 468A.025
Hist.: DEQ 37, f. 2-15-72, ef. 3-1-72; DEQ 8-1988, f. & cert. ef. 5-19-88 (corrected 9-30-88); DEQ 24-1991, f. & cert. ef. 11-13-91; DEQ 4-1993, f. & cert. ef. 3-10-93; DEQ 14-1999, f. & cert. ef. 10-14-99, Renumbered from 340-031-0015; DEQ 6-2001, f. 6-18-01, cert. ef. 7-1-01; DEQ 5-2010, f. & cert. ef. 5-21-10; DEQ 5-2011, f. 4-29-11, cert. ef. 5-1-11