Utah Administrative Code
Topic - Environmental Quality
Title R307 - Air Quality
Rule R307-105 - General Requirements: Emergency Controls
Section R307-105-1 - Air Pollution Emergency Episodes
Current through Bulletin 2024-06, March 15, 2024
(1) Determination of an episode and its extent or stage shall be made by the director taking into consideration the levels of pollutant concentrations contained at 40 CFR Section 51.151 and 40 CFR Section 51, Appendix L, and summarized in the table below:
TABLE AIR POLLUTION EPISODE CRITERIA (values in micrograms/cubic meter unless stated otherwise) |
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POLLUTANT |
ALERT |
WARNING |
EMERGENCY |
NEVER TO BE EXCEEDED |
SULFUR DIOXIDE |
800 |
1,600 |
2,100 |
2,620 |
24-hour average |
(0.3 ppm) |
(0.6 ppm) |
(0.8 ppm) |
(1.0 ppm) |
PM10 |
3 50 |
420 |
500 |
600 |
24-hour average | ||||
CARBON MONOXIDE | ||||
8-hour average |
17,000 ( 15 ppm) |
34,000 30 ppm) |
46,000 (40 ppm) |
57,500 (50 ppm) |
4-hour average |
86 , 300 (75 ppm) |
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1-hour average |
144 ,000 (125 ppm) |
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OZONE | ||||
1-hour average |
400 ( 0.2 ppm) |
800 (0.4 ppm) |
1,000 (0.5 ppm) | |
2-hour average |
1 , 2 00 (0 . 6 ppm) |
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NITROGEN DIOXID |
E 1130 |
2,260 |
3,000 |
3,750 |
1-hour average |
(0.6 ppm) |
(1.2 ppm) |
(1.6 ppm) |
(2.0 ppm) |
NITROGEN DIOXID |
E 282 |
565 |
750 |
938 |
24-hour average |
(0.15 ppm) |
(0.3 ppm) |
(0.4 ppm) |
(0.5 ppm) |
An air pollution alert, air pollution warning, or air pollution emergency will be declared when any one of the above pollutants reaches the specified levels at any monitoring site.
In addition to the levels listed for the above pollutants, meteorological conditions are such that pollutant concentrations can be expected to remain at the above levels for twelve (12) or more hours or increase, or in the case of ozone, the situation is likely to reoccur within the next 24-hours unless control actions are taken.
ALERT The Alert level is that concentration at which first stage control action is to begin.
WARNING The warning level indicates that air quality is continuing to degrade and that additional control actions are necessary.
EMERGENCY The emergency level indicates that air quality is continuing to degrade toward a level of significant harm to the health of persons and that the most stringent control actions are necessary.
(2) The director shall also take into consideration, to determine an episode and its extent, rate of change of concentration, meteorological forecasts, and the geographical area of the episode, including a consideration of point and area sources of emission, where applicable.