Rhode Island Code of Regulations › Title 250 - Department of Environmental Management › Chapter 120 - Air Resources › Subchapter 05 - Air Pollution Control › Part 10 - Air Pollution Episodes › Section 250-RICR-120-05-10.5 - Episode Criteria

Current through June 14, 2024
A. Conditions
				  justifying the proclamation of an air pollution alert, air pollution warning or
				  air pollution emergency shall be deemed to exist whenever the Director
				  determines that the accumulation of air pollutants in any place is attaining or
				  has attained levels which could, if such levels are sustained or exceeded, lead
				  to a substantial threat to the health of persons. In making this determination,
				  the Director will be guided by the following criteria:
1. An air pollution forecast is an internal
				  watch by the Office of Air Resources actuated by a National Weather Service
				  advisory that an Atmospheric Stagnation Advisory is in effect or an equivalent
				  local forecast of a stagnant atmospheric condition is in effect.
2. The Air Pollution Alert level is that
				  concentration of pollutants at which first stage control actions are necessary.
				  An Alert will be declared when any one of the following levels is reached at
				  any monitoring site and meteorological conditions are such that pollutant
				  concentrations can be expected to remain at the levels specified in
				  §§
											10.5(A)(2)(a) through
				  (e) of this Part for twelve (12) or more
				  hours or increase above these levels unless control actions are taken:
a. Sulfur Dioxide or
				  SO2 - 800 µg/m³ (0.3ppm), 24-hour
				  average.
b. Particulate matter less
				  than 10 microns in diameter or PM10 - 350
				  µg/m3, 24-hour average.
c. CO - 17 mg/m3
				  (15 ppm), 8-hour average.
d. Ozone
				  (O3) - 400 µg/m³ (0.2 ppm), 1-hour
				  average.
e. Nitrogen Dioxide or
				  NO2 - 1130 µg/m³ (0.6 ppm), 1-hour average or
				  282 µg/m³ (0.15 ppm), 24-hour average.
3. The Air Pollution Warning level indicates
				  that air quality is continuing to degrade and that additional control actions
				  are necessary. A Warning will be declared when any one of the following levels
				  is reached at any monitoring site and meteorological conditions are such that
				  pollutant concentrations can be expected to remain at the levels specified in
				  §§
											10.5(A)(3)(a) through
				  (e) of this Part for twelve (12) or more
				  hours or increase above these levels unless control actions are taken:
a. Sulfur Dioxide or
				  SO2 - 1600 µg/m³ (0.6ppm), 24-hour
				  average.
b. Particulate matter less
				  than 10 microns in diameter or PM10 - 420
				  µg/m3, 24-hour average.
c. Carbon Monoxide or CO - 34 mg/m³ (30
				  ppm), 8-hour average.
d.
				  Ozone(O3) - 800 µg/m3
				  (0.4 ppm), 1-hour average.
e.
				  Nitrogen Dioxide or NO2 - 2260 µg/m³ (1.2
				  ppm), 1-hour average or 565 µg/m³ (0.3 ppm), 24-hour
				  average.
4. The Air
				  Pollution Emergency level indicates that air quality is continuing to degrade
				  to a level that should never be reached and that the most stringent control
				  actions are necessary. An Emergency will be declared when any one of the
				  following levels is reached at any monitoring site and meteorological
				  conditions are such that pollutant concentrations can be expected to remain at
				  the levels specified in §§
											10.5(A)(4)(a) through
				  (e) of this Part for twelve (12) or more
				  hours or increase above these levels unless control actions are taken:
a. SO2 - 2100
				  µg/m³ (0.8 ppm), 24-hour average.
b. Particulate matter less than 10 microns in
				  diameter or PM10 - 500 µg/m3, 24-hour
				  average.
c. Carbon Monoxide or CO -
				  46 mg/m³ (40 ppm), 8-hour average.
d. Ozone(O3) - 1000
				  µg/m³ (0.5 ppm), 1-hour average.
e. Nitrogen Dioxide or
				  NO2 - 3000 µg/m3 (1.6
				  ppm), 1-hour average of 750 µg/m³ (0.4 ppm), 24-hour
				  average.
5. Termination,
				  once declared, any status reached by application of these criteria will remain
				  in effect until the criteria for that level are no longer met. At such time,
				  the next lower status will be assumed, or the episode will be declared
				  over.