WAC 173-476-150. Ambient air quality standard for ozone

(1) Standard for ozone. The three-year average of the annual fourth highest daily maximum eight-hour average concentration of ozone in the ambient air must not exceed 0.070 ppmv. (2) Measurement method. The levels of ozone in the ambient air must be measured by: (a) A FRM based on 40 C.F.R. Part 50, Appendix D and designated according to 40 C.F.R. Part 53; or (b) A FEM designated according to 40 C.F.R. Part 53. (3) Interpretation method. The interpretation method found in 40 C.F.R. Part 50, Appendix U must be followed.