§ 3-28. Same—Episode criteria.

(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 contaminants at any sampling location is attaining, or has attained, levels which could, if such levels are sustained or exceeded, lead to a threat to the health of the public. In making this determination, the director will be guided by the following criteria:

(1)

Air pollution forecast. The issuance of a weather bureau high pollution potential advisory or the equivalent indication by a local weather bureau meteorologist that a stagnant atmospheric condition will exist for the next 36 hours.

(2)

Air pollution alert. The average SO ₂ level for the previous 24 consecutive hours equals 0.3 ppm (800 micrograms per cubic meter) or the average two-hour soiling index for the previous 24 consecutive hours equals three COH/1,000 linear feet, or the suspended particulate level for the previous 24 consecutive hours equals 375 micrograms per cubic meter, or the product of the average soiling index and the SO ₂ concentration for the previous 24 consecutive hours equals 0.20 parts per million (ppm), or the product of the average suspended particulate and SO ₂ concentration (micrograms per cubic meter) for the previous 24 consecutive hours equals 65,000, or the average CO level for the previous eight consecutive hours equals 15 ppm, or the average Ox level for the preceding one hour equals 0.1 ppm, or the average NO ₂ concentration for the preceding one hour equals 0.6 ppm, or the average NO ₂ concentration for the preceding 24 consecutive hours equals 0.15 ppm, and the local meteorologist predicts no major changes in existing adverse meteorological conditions for at least an additional 12 hours.

(3)

Air pollution warning. The average SO ₂ level for the previous 24 consecutive hours equals 0.60 ppm (1,600 micrograms per cubic meter), or the average two-hour soiling index for the previous 24 consecutive hours equals five COH/1,000 linear feet, or the suspended particulate level for the previous 24 consecutive hours equals 624 micrograms per cubic meter, or the product of the average soiling index and SO ₂ concentration for the previous 24 consecutive hours equals 0.80 ppm, or the product of the average suspended particulate and SO ₂ concentration (micrograms per cubic meter) for the previous 24 consecutive hours equals 261,000, or the average CO level for the previous eight consecutive hours equals 30 ppm, or the average Ox level for the preceding one hour equals 0.4 ppm, or the average NO ₂ concentration for the preceding one hour equals 1.2 ppm, or the average NO ₂ concentration for the preceding 24 consecutive hours equals 0.3 ppm, and the local meteorologist predicts no major changes in existing adverse meteorological conditions for the next 12 hours.

(4)

Air pollution emergency. The average SO ₂ level for the previous 24 consecutive hours equals 0.8 ppm (2,100 micrograms per cubic meter), or the average two-hour soiling index for the previous 24 consecutive hours equals seven COH/1,000 linear feet, or the suspended particulate level for the previous 24 consecutive hours equals 875 micrograms per cubic meter, or the product of the average soiling index and the SO ₂ concentration for the previous 24 consecutive hours equals 1.2 ppm, or the product of the average suspended particulate and the SO ₂ concentration (micrograms per cubic meter) for the previous 24 consecutive hours equals 393,000, or the average CO level for the previous eight consecutive hours equals 40 ppm, or the average Ox level for the preceding one hour equals 0.6 ppm, or the average NO ₂ concentration for the preceding one hour equals 1.6 ppm, or the average NO ₂ concentration for the preceding 24 consecutive hours equals 0.4 ppm, and the local meteorologist predicts no major changes in existing adverse meteorological conditions for at least an additional 12 hours.

(b)

The provisions of section 3-27 notwithstanding, the director may declare any status prescribed therein on the basis of deterioration of air quality to the criteria levels alone and without the issuance of a high air pollution potential advisory or equivalent advisory from a local weather bureau meteorologist if deemed necessary to protect the public health.

(c)

Once declared, any status established on the basis of section 3-27, this section, and sections 3-29 and 3-30 shall remain in effect until the criteria for that level is no longer met. At such time the next lower status will be assumed.

(Code 1964, § 2A-28; Code 1988, § 3-29; Ord. No. 52677, § 1, 2-28-1974)