ISSUES REGARDING THE OZONE AIR-QUALITY STANDARDS

We have proposed a robust two-component testing scheme for attainment status. It aims at reducing the impact of fluctuations, such as the 1988 heat wave, that push the long-standing attainment areas into nonattainment. The scheme is not protective of the status of attainment areas with an upward ozone trend, be the trend due to a change in ozone-precursor emissions or persistent adverse meteorology. The scheme is applicable to an ozone standard that uses an order statistic like the annual second-highest value or the annual 95th percentile. We also discuss the stringency of the California ozone air quality standard and the nonattainment-transitional status introduced by the Staff of the California Air Resource Board.