Changes focus on improving efficiency and delivering timely, transparent permit decisions.
Learn about San Francisco County - its climate, potential air pollution concerns, and current air quality. You can also view upcoming Air District events in San Francisco County and read about local efforts to improve air quality.
Changes focus on improving efficiency and delivering timely, transparent permit decisions.
The Air District has fined Chemtrade West US LLC $160,000 for air quality violations at its sulfuric acid manufacturing plant in Richmond, which is connected to the Chevron Richmond refinery. Chemtrade supplies various chemical products to industry, including sulfuric acid, which is a byproduct of refining crude oil.
The Air District is lifting an air quality advisory for wildfire smoke that was originally scheduled to last through tomorrow, Wednesday, August 27.
The Air District has announced a $13.3 million grant to the San Mateo County Transit District toward the installation of new high-capacity electric bus charging infrastructure at its San Carlos facility. This SamTrans project will help accelerate the transition of the SamTrans bus fleet to zero-emission technology and improve air quality in communities most affected by air pollution.
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San Francisco County rests at the northern end of the San Francisco Peninsula, bounded by San Mateo County in the south, the Pacific Ocean to the west, San Francisco Bay to the east, and the Golden Gate Bridge to the north. Three San Francisco County representatives sit on the Air District’s Board of Directors.
Because most of San Francisco's landscape is below 200 feet, the marine layer flows across most of the city, creating a cool and windy climate. The southeastern portion of the county, however, tends to be warmer and sunnier, with fewer foggy days. In the winter, average daily temperatures are mild overnight and moderate during the day, while summertime temperatures tend to remain moderate throughout the season. The highest wind speeds are focused along the western coast and generally mild throughout the county. Rainfall averages about 20 inches per year, with the highest amounts reported on the western coast.
Interactive Air Monitoring Stations Map
Ozone and fine particle pollution, or PM2.5, are the major regional air pollutants of concern in the San Francisco Bay Area. Ozone is primarily a problem in the summer, and fine particle pollution in the winter.
In San Francisco, ozone almost never exceeds health standards and PM2.5 only exceeds the national standard once or twice each year, generally. Being surrounded by water on three sides keeps temperatures within a narrow range, whereby winter low temperatures rarely reach freezing and summer high temperatures stay well below levels where ozone would form and become unhealthy.
Last Updated: 4/21/2017