326 IAC 1-5-4
326 IAC 1-5-4 Episode levels; alerts; warnings; emergencies
Cite as Ind. Admin. Code tit. 326, r. 1-5-4
Sec. 4. (a) Air pollution alert: When the concentration of the contaminants listed below reaches an alert level, first stage control action must
begin. An alert will be declared by the commissioner when any one of the following levels is reached at any sampling site:
(1) SO2: 0.30 parts per million (ppm) 800 micrograms per cubic meter (μg/m3), 24-hour
average.
(2) Particulate: 375 μg/m3, 24-hour average. A measurement of 3.0 COH (Coefficient of haze), 24-hour average
indicates the possibility of an alert level; however, the 375 limit must be reached before an alert may be declared.
(3) CO: 15 ppm (17 mg/m3), 8-hour average.
(4) O3: 0.2 ppm (400 μg/m3), 1-hour average.
(5) NOx: 0.6 ppm (1130 μg/m3), 1-hour average, or 0.15 ppm (282 μg/m3), 24-hour average.
(6) PM10: 350 μg/m3, 24-hour average.
(b) Air pollution warning: When the concentration of contaminants listed below indicates that air quality is continuing to degrade, second
stage control actions must begin. A warning will be declared by the commissioner when any one of the following levels is reached at any
representative sampling site and meteorological conditions are such that pollutant concentrations can be expected to remain at the above levels for
twelve (12) or more hours or to increase, or in the case of oxidants, the situation is likely to recur within the next 24-hours unless control actions
are taken:
(1) SO2: 0.6 ppm (1600 μg/m3), 24-hour average.
(2) Particulate: 625 μg/m3, 24-hour average. A measurement of 5.0 COH's, 24-hour average indicates the
possibility of a warning; however, the 625 limit must be reached before a warning may be declared.
(3) CO: 30 ppm (34 mg/m3), 8-hour average.
(4) O3: 0.40 ppm (800 μg/m3), 1-hour average.
(5) NOx: 1.2 ppm (2260 μg/m3), 1-hour average, or 0.30 ppm (565 μg/m3), 24-hour average.
(6) PM10: 420 μg/m3, 24-hour average.
(c) Air pollution emergency: The commissioner shall request that the governor of the state of Indiana declare an emergency pursuant to
IC 13-1-1-7 [ IC 13-1 was repealed by P.L.1-1996, SECTION 99, effective July 1, 1996.] and IC 13-7-12
[ IC 13-7 was repealed by P.L.1-1996, SECTION 99, effective July 1, 1996.] when one of the criteria contaminants listed below
reaches the following levels and (1) the concentrations of the pollutants are continuing to increase, or (2) the commissioner determines that, because
of meteorological or other factors, the concentrations may remain at such levels or may continue to increase:
(1) SO2: 0.8 ppm (2100 μg/m3), 24-hour average.
(2) Particulate: 875 μg/m3, 24-hour average. A measurement of 7.0 COH's, 24-hour average indicates the
possibility of an emergency; however, the 875 limit must be reached before an emergency may be declared.
(3) CO: 40.0 ppm (46 mg/m3), 8-hour average.
(4) O3: 0.50 ppm (1000 μg/m3), 1-hour average.
(5) NOx: 1.6 ppm (3000 μg/m3), 1-hour average, or .4 ppm (750 μg/m3), 24-hour
average.
(6) PM10: 500 μg/m3, 24-hour average.