Air Quality

To improve the quality of air for all

The South Coast Air Basin including Los Angeles County is frequently cited as one of the regions with the worst air quality in the country. This is due primarily to the transportation sector and high concentrations of industrial and commercial operations, in addition to the presence of mountain ranges trapping noxious gases inland. Though Santa Monica is located on the coast, the region is still subject to high emissions levels and poor air quality that can cause health risks such as asthma, particularly among children.
Ozone concentrations contribute to urban smog and are particularly high on hot days.

How are we doing? 

The South Coast Air Quality Management District (SCAQMD) is the air pollution control agency that measures and reports air quality in and around the urban areas of Los Angeles County. Santa Monica’s air quality is monitored by the Northwest Coastal L.A. County site (see map of SCAQMD monitoring site). 
The South Coast Air Basin including Los Angeles County is frequently cited as one of the regions with the worst air quality in the country. This is due primarily to the transportation sector and high concentrations of industrial and commercial operations, in addition to the presence of mountain ranges trapping noxious gases inland. Though Santa Monica is located on the coast, the region is still subject to high emissions levels and poor air quality that can cause health risks such as asthma, particularly among children.
Ozone concentrations contribute to urban smog and are particularly high on hot days.

Days Exceeding Federal Air Quality Standards

This indicator is measured by the number of days with ozone levels exceeding current Federal standards based on SCAQMD annual air quality report. In 2014, the Federal standards changed from .075 parts per million (ppm) during an eight-hour period to .07 parts per million (ppm).

Air Quality Index Median

This indicator measures the median for daily air quality index (AQI) as reported by the US Environmental Protection Agency (EPA). This indicator reflects Los Angeles County's median AQI. The EPA does not measure Santa Monica's air quality separately. 

This guide shows the different categories for values of AQI. This guide is on the EPA's website. 

For more information regarding AQI, please visit the following website.  


Days Unhealthy for Sensitive Groups

This indicator measures the number of days considered as "unhealthy for sensitive groups." This data reflects the Los Angeles County data based on the US EPA's air quality reports. A day is categorized as unhealthy for sensitive groups if the daily AQI measures above 100. 

Purple Air Sensor

To measure local air quality, residents and organizations can install a Purple Air sensor inside or outside of their property. The sensor measure AQI. Real-time data is collected and published on the Purple Air website.  

What can I do to help?

The quality of the air we breathe is linked to almost all aspects of our daily lives. Energy conservation is a key to reducing air pollution because air pollution is created anytime energy is burned. So, choosing to take your car for short errands instead of walking or biking; or, forgetting to turn off your lights—all contributes to air pollution.
  • Simple actions to reduce our consumption of energy and resources also go a long way to improving air quality.
  • Turn off lights and appliances when not in use to save energy.
  • Conserve water to help save energy which in turn helps to clean the air.
  • Drive less. Walk, bike, and bus more.
  • Switch to an alternative fuel car – there are so many choices now -- electric, hybrid, hydrogen fuel cell, or cng.
  • Go solar.
  • Reuse and recycle.
  • For more tips on how to improve our air and everyone's quality of life, check out this video, "Do One Thing ".