State and federal governments have set health standards for pollutants, specifying levels beyond which the air is unhealthful. California’s state standards for air pollutants are more stringent than the federal government’s. It is up to each individual state to determine if they want to set tougher standards. Standards are set to provide an adequate margin of safety in the protection of public health. Under the federal Clean Air Act, EPA must base standards solely on health considerations and not economics or technology. In the event of extremely bad and/or dangerous air quality conditions, the government will alert the general public via the media. Various levels of smog episodes are reported for the pollutant ozone. The declaration of a first, second or third stage smog alert is based on the degree of health risk. The protective actions help to reduce exposure to unhealthful levels of ozone, but those who are especially sensitive should contact their physician for more specific advice. Generally, in the event of a smog alert, outdoor activities should be scheduled for morning or early evening hours to avoid the mid-day peak when ozone levels are at their highest. Hourly updates on air pollution levels are available to the public through the AQMD’s toll-free, taped telephone information service. The number for residents of Los Angeles is (800) 242-4022, (800) 445-3826 for Orange County and (800) 322-4710 for Riverside/San Bernardino counties. AQMD also provides a live, toll-free line at (800) 242-4666, where callers can ask specific questions about air pollution conditions.