7 Del. Admin. Code § 1103-8.0

Current through Register Vol. 27, No. 12, June 1, 2024

Section 1103-8.0 - Nitrogen Dioxide

8.1 The national primary and secondary air quality standards for oxides of nitrogen (nitrogen dioxide indicator) are as follows:

8.1.1 The primary 1-hour air quality standard for oxides of nitrogen is 100 parts per billion (ppb), 1-hour average concentration, measured in the ambient air as nitrogen dioxide. Compliance with the 1-hour standard is demonstrated when the three-year average of the 98th percentile of the daily maximum 1-hour average concentration is less than or equal to 100 ppb, as determined with 40 CFR Part 50, Appendix S, Interpretation of the Primary Air Quality Standards for Oxides of Nitrogen (Nitrogen Dioxide), July 1, 2019

8.1.2 The primary annual air quality standard for oxides of nitrogen is 53 parts per billion (ppb), annual average concentration, measured in the ambient air as nitrogen dioxide. The primary annual air quality standard is demonstrated when the average annual concentration in a calendar year is less than or equal to 53 ppb, as determined with 40 CFR Part 50, Appendix S, Interpretation of the Primary Air Quality Standards for Oxides of Nitrogen (Nitrogen Dioxide), July 1, 2019.

8.1.3 The secondary annual air quality standard for oxides of nitrogen is 53 parts per billion (ppb), annual arithmetic mean concentration, measured in the ambient air as nitrogen dioxide. The secondary ambient air quality standard is demonstrated when the annual arithmetic mean concentration in a calendar year is less than or equal to 0.053 ppm. 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.

8.2 The primary and secondary air quality standards for nitrogen dioxide are as set forth in 40 CFR Part 50.11, July 1, 2019.

02/01/1981

7 Del. Admin. Code § 1103-8.0

17 DE Reg. 741 (1/1/2014)
26 DE Reg. 120 (8/1/2022) (Final)