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Talk:National Ambient Air Quality Standards

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Why not include the entire standard?

[edit]

e.g., here is the

National primary ambient air quality standards for sulfur oxides (sulfur dioxide).

§ 50.17

(a) The level of the national primary 1-hour annual ambient air quality standard for oxides of sulfur is 75 parts per billion (ppb, which is 1 part in 1,000,000,000), measured in the ambient air as sulfur dioxide (SO2).

(b) The 1-hour primary standard is met at an ambient air quality monitoring site when the three-year average of the annual (99th percentile) of the daily maximum 1-hour average concentrations is less than or equal to 75 ppb, as determined in accordance with appendix T of this part.

(c) The level of the standard shall be measured by a reference method based on appendix A or A-1 of this part, or by a Federal Equivalent Method (FEM) designated in accordance with part 53 of this chapter.

[75 FR 35592, June 22, 2010]


The standards are omitted for oxides of nitrogen (other than NO2)

[edit]

The article currently cites only the secondary limit, 0.053 parts per million (53 parts per billion) of nitrogen dioxide and omits the primary limits on oxides of nitrogen.


The cited legal authority specifies limits for "oxides of nitrogen" measured in parts per billion, including a

primary limit of one-hour standard of 100 ppb and

primary limit of an annual average of 53 ppb.


So, could there be value in including the primary limits?


Here's the law cited

CFR Title 40 - Protection of Environment (2017) (Accessed 2018 July 31)

https://www.gpo.gov/fdsys/pkg/CFR-2017-title40-vol2/xml/CFR-2017-title40-vol2-sec50-11.xml

§ 50.11 National primary and secondary ambient air quality standards for oxides of nitrogen (with nitrogen dioxide as the indicator).


(a) The level of the national primary annual ambient air quality standard for oxides of nitrogen is 53 parts per billion (ppb, which is 1 part in 1,000,000,000), annual average concentration, measured in the ambient air as nitrogen dioxide.


(b) The level of the national primary 1-hour ambient air quality standard for oxides of nitrogen is 100 ppb, 1-hour average concentration, measured in the ambient air as nitrogen dioxide.


(c) The level of the national secondary ambient air quality standard for nitrogen dioxide is 0.053 parts per million (100 micrograms per cubic meter), annual arithmetic mean concentration.


Ocdcntx (talk) 15:43, 31 July 2018 (UTC)[reply]