On October 1, 2015, the U.S. Environmental Protection Agency (EPA) announced a new eight-hour standard of 70 ppb for ground-level ozone, one of the principal components of smog. For more information, see New Ozone Standard.

To view exceedances of standards, see Days Exceeding Ozone and Particulate Standards.

Air quality standards define clean air. They tell us how much of a substance can be in the air without causing harm, based on proven scientific and medical research. Both the federal and state governments set air quality standards. In most cases, California’s standards are more protective of health. The Attainment Designation tells us whether our air meets these health standards.

Federal standards have been established for seven pollutants:

  1. carbon monoxide
  2. lead
  3. nitrogen dioxide
  4. ozone
  5. respirable particulate matter less than 10 microns in diameter (PM10)
  6. fine particulate matter less than 2.5 microns in diameter (PM2.5), and
  7. sulfur dioxide.

California state standards exist for all of these, plus four more:

  1. sulfates
  2. hydrogen sulfide
  3. vinyl chloride (chloroethene), and
  4. visibility reducing particles.

These are the only pollutants – out of hundreds in our air – for which standards have been set. There is not enough known about the health effects of other pollutants to set air quality standards. View the State and Federal Ambient Air Quality Standards.

Santa Barbara County was designated unclassifiable/attainment for the 2015 revised federal 8-hour ozone standard on April 30, 2018.  The County is designated nonattainment-transitional for the state ozone standard, and also violates the state PM10 standard. The County is unclassifiable/attainment for the federal PM2.5 standard and unclassified for the state PM2.5 standard.

To view historical statistics on ozone and particle pollution levels in Santa Barbara County and other areas of the state, visit the California Air Resources Board air quality data base.

Santa Barbara County Attainment/Nonattainment Classification Summary

PollutantAveraging TimeCalifornia StandardsNational Standards
ConcentrationAttainment StatusConcentrationAttainment Status
8 hour0.070 ppmNA-T**0.070 ppmU/A
1 hour0.09 ppm (180 µg/m3)NA-T**
Carbon Monoxide
8 hour9.0 ppm (10 mg/m3)A9.0 ppm (10 m/m3)A
1 hour20.0 ppm (23 mg/m3)A35.0 ppm (40 µg/m3)A
Nitrogen Dioxide
annual average0.030 ppm (56 µg/m3)A53 ppbU/A
1 hour0.18 ppm (338 µg/m3)A100 ppbU/A
Sulfur Dioxide
annual averageRevoked
24 hour0.04 ppm (105 µg/m3)ARevoked
1 hour0.25 ppm (655 µg/m3)A75 ppb*

Particulate Matter (PM10)

annual arithmetic mean20 µg/m3NrevokedA
24 hour50 µg/m3N150 µg/m3A

Particulate Matter – Fine (PM2.5)

annual arithmetic mean12µg/m3U12.0 µg/m3U/A
24 hour35 µg/m3U/A
24 hour25 µg/m3A
calendar quarter1.5 µg/m3A
30 day average1.5 µg/m3A
Rolling 3-month Average0.15 µg/m3U
Hydrogen Sulfide
1 hour0.03 ppm (42 µg/m3)A
Vinyl Chloride (chloroethene)
24 hour0.010 ppm (26 µg/m3) 
Visibility Reducing Particles
8 hour (1000 to 1800 PST) A

A=Attainment;  N=Nonattainment;  U=Unclassified;  U/A=Unclassifiable/Attainment;  NA-T=Nonattainment-Transitional

mg/m3=milligrams per cubic meter;  µg/m3=micrograms per cubic meter;  ppm=parts per million;  ppb=parts per billion;  — = No Standard


*  EPA has not yet made final designations on attainment status.  For more information, see EPA’s website.

** A region is designated Nonattainment-transitional when the ozone standard has not been exceeded more than three times at any one location during the last year.