PDFWAC 173-481-110
Ambient action levels.
(1) All sampling to determine compliance with these action levels shall be conducted in locations and during time periods consistent with protecting vegetation of the type and in areas covered by this chapter.
(2) Gaseous fluorides in the ambient air calculated as HF at standard conditions shall not exceed:
(a) Two and nine-tenths micrograms per cubic meter (2.9 µg/m3) average for any nonoverlapping twenty-four consecutive hours;
(b) One and seven-tenths micrograms per cubic meter (1.7 µg/m3) average for any seven consecutive days;
(c) Eighty-four one-hundredths micrograms per cubic meter (0.84 µg/m3) average for any thirty consecutive days;
(d) Five-tenths micrograms per cubic meter (0.5 µg/m3) average for the growing season.