Section 424 - OZONE STANDARD424.1 The average eight hour concentration of ozone measured at an ambient air monitoring station shall not exceed 0.080 ppm (157 micrograms per cubic meter) as determined under the following conditions: 424.11 The 3-year average of the annual fourth highest daily maximum 8-hour average concentrations shall be used to determine compliance with this standard;424.12 All hourly measurements must start on the clock hour. Wash. Admin. Code Northwest Clean Air Agency, 400, 424
AMENDED: October 13, 1982, April 14, 1993, July 14, 2005