Title 18 . Environmental Conservation

Chapter 50 . Administrative Enforcement

Section 10. Ambient air quality standards

18 AAC 50.010. Ambient air quality standards

The standards for concentrations of air pollutants in the ambient air, measured or predicted by an analytical method described in 18 AAC 50.215, are established as follows:

(1) for PM-10:

(A) expected annual arithmetic mean of 50 micrograms per cubic meter; and

(B) 24-hour average of 150 micrograms per cubic meter, with this standard being attained when the expected number of days in a calendar year with a 24-hour average concentration above 150 micrograms per cubic meter is less than or equal to one day;

(2) for sulfur oxides, measured as sulfur dioxide:

(A) annual arithmetic mean of 80 micrograms per cubic meter;

(B) 24-hour average of 365 micrograms per cubic meter not to be exceeded more than once each year; and

(C) three-hour average of 1300 micrograms per cubic meter not to be exceeded more than once each year;

(3) for carbon monoxide:

(A) eight-hour average of 10 milligrams per cubic meter not to be exceeded more than once each year; and

(B) one-hour average of 40 milligrams per cubic meter not to be exceeded more than once each year;

(4) for ozone: one-hour average of 235 micrograms per cubic meter, with this standard being attained when the expected number of days in a calendar year with a minimum hourly average concentration above 235 micrograms per cubic meter is less than or equal to one day;

(5) for nitrogen dioxide: annual arithmetic mean of 100 micrograms per cubic meter;

(6) for lead: quarterly arithmetic mean of 1.5 micrograms per cubic meter;

(7) for reduced sulfur compounds, expressed as sulfur dioxide: 30-minute average of 50 micrograms per cubic meter not to be exceeded more than once each year; and

(8) for ammonia: 2.1 milligrams per cubic meter, averaged over any consecutive eight hours not to be exceeded more than once each year.

History: Eff. 1/18/97, Register 141; am 6/21/98, Register 146; am 10/1/2004, Register 171

Authority: AS 46.03.020

AS 46.14.010

AS 46.14.030

Sec. 30, ch. 74,

SLA 1993