Concentrations of nitrogen dioxide in ambient air as measured by a reference method based on appendix F to 40 CFR part 50 or by a Federal equivalent method (FEM) designated in accordance with 40 CFR part 53 must not exceed:

1. (1) 0.053 ppm as an annual average concentration for any calendar year at any site. The standard is met when the annual average concentration in a calendar year is less than or equal to 0.053 ppm, as determined in accordance with appendix S of 40 CFR part 50 for the annual standard.
2. (2) 0.100 ppm as a 3-year average of the annual 98th percentile of the 1-hour daily maximum concentrations recorded at any monitoring site. The standards is met when the three-year average of the annual 98th percentile of the daily maximum 1-hour average concentration is less than or equal to 0.100 ppm, as determined in accordance with appendix S of 40 CFR part 50 for the 1-hour standard.

3. (3) 0.053 ppm as an annual arithmetic mean concentration as determined in accordance with Appendix S of 40 CFR part 50. The secondary standard is attained when the annual arithmetic mean concentration in a calendar year is less than or equal to 0.053 ppm, rounded to three decimal places (fractional parts equal to or greater than 0.0005 ppm must be rounded up). To demonstrate attainment, an annual mean must be based upon hourly data that are at least 75 percent complete or upon data derived from manual methods that are at least 75 percent complete for the scheduled sampling days in each calendar quarter.

   [NOTE: This rule is included in the State of Oregon Clean Air Act Implementation Plan that EQC adopted under OAR 340-200-0040.]

   [NOTE: View a PDF of referenced appendices by clicking on "Tables" link below.]

   [ED. NOTE: To view attachments referenced in rule text, click here for PDF copy.]

Statutory/Other Authority

ORS 468.020 & 468A

Statutes/Other Implemented

ORS 468A.025 & 468A.035

History

DEQ 13-2019, amend filed 05/16/2019, effective 05/16/2019
DEQ 7-2015, f. & cert. ef. 4-16-15
DEQ 11-2013, f. & cert. ef. 11-7-13
DEQ 6-2001, f. 6-18-01, cert. ef. 7-1-01
DEQ 14-1999, f. & cert. ef. 10-14-99, Renumbered from 340-031-0040
DEQ 4-1993, f. & cert. ef. 3-10-93
DEQ 24-1991, f. & cert. ef. 11-13-91
DEQ 8-1988, f. & cert. ef. 5-19-88 (corrected 9-30-88)
DEQ 37, f. 2-15-72, ef. 3-1-72