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Louisiana SIP: LAC 33:III Ch. 7 - Table 1a - Secondary Ambient Air Quality Standards; SIP effective 1989-05-08 (LAc49) and 1989-08-14 (LAc50) to 2011-08-03 (LAd34 - Moved to Section 711 and revised [adds PM-2.5])

Regulatory Text: 
Louisiana Administrative Code, Title 33 ENVIRONMENTAL QUALITY, Part III Air (LAC 33:III) 

Chapter 7. Ambient Air Quality

TABLE 1a : Secondary Ambient Air Quality Standards

(Approved by EPA 03/08/89 (54 FR 09795) at 52.970(c)(49) effective 05/08/89.  Revisions approved by EPA 06/15/89 at 52.970(c)(50) effective 08/14/89.)

Chapter 7, TABLE 1a: Secondary Ambient Air Quality Standards

Standards Maximum Permissible
PM10 50 µg/m3 (Annual arithmetic mean)
150 ug/m3 (Maximum 24-hour concentration not to
be exceeded more than once per year)
Dioxide (SO2)
1300 µg/m3 (Maximum 3 hour concentration not to
be exceeded more than once per year)
Monoxide (CO)
10,000 µg/m3 or 9 ppm (Maximum 8 hour concentration not to be exceeded more than once per year)
40,000 µg/m3 or 35 ppm (Maximum 1 hour concentration not to be exceeded more than once per year)
Ozone 235 µg/m3 (0.12 ppm) Thestandard is attained
when the expected number of days per calendar
year with maximum hourly average concentration
above 0.12 ppm [235 micrograms per cubic meter
(ug/m3)] is equal to or less than one as
determined by 40 CFR 50 Appendix H.
Dioxide (NO2)
100 µg/m3 (0.05 ppm) (annual arithmetic mean)
Lead 1.5 µg/m3 (Maximum arithmetic mean averaged over a calendar quarter)

The contribution of any contaminant by a single source property shall be measured as the difference between the upwind level and the downwind level for the property, using methods approved by the administrative authority, or by the use of suitable engineering techniques such as source-dispersion calculations.

National secondary ambient air quality standards define levels of air quality which the Administrator of the Environmental Protection Agency judges to be necessary to protect the public welfare from any known or anticipated adverse effects of a pollutant.

   AUTHORITY NOTE:  Promulgated in accordance with R.S. 30:1084.
   HISTORICAL NOTE:  Promulgated by the Department of Environmental Quality, Office of Air Quality and Nuclear Energy, Air Quality Division in LR 13:741 (December 1987) as amended LR 14:348 (June 1988).

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