California Home Page Air Resources Board Home Page Air Quality Data Home Page Search the ARB Web Site ARB Web Site Map Software Contact the Air Resources Board Data Descriptions Page
State of California California Air Resources Board
January - July 8th
Year 2001 Ozone Summary
for Selected California Monitoring Sites and Regions
   

Previous Ozone Summaries

Greater Sacramento Planning Area
County Site Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
Sacramento Folsom-
50 Natoma Street
1998 3 0 2 0.10 0.09
1999 9 0 5 0.12 0.10
2000 3 1 2 0.13 0.10
2001** 21 3 17 0.14 0.11

Sacramento Sacramento-
Del Paso Manor
1998 1 0 0 0.10 0.08
1999 1 0 0 0.10 0.08
2000 4 0 3 0.12 0.10
2001** 11 1 8 0.14 0.11

Sacramento Sloughhouse 1998 1 0 0 0.10 0.08
1999 4 0 0 0.12 0.08
2000 6 2 6 0.14 0.10
2001** 19 0 18 0.12 0.10
Region* Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
Greater Sacramento Planning Area
Summary
1998 7 0 5 0.10 0.09
1999 15 0 10 0.12 0.10
2000 14 5 11 0.14 0.11
2001** 27 3 26 0.14 0.11
* For the Regional summary statistics, the number of exceedance days equals the number of distinct days on which the relevant standard was exceeded at any monitoring site in the area.  If the standard was exceeded at more than one site on a given day, it only counts as one exceedance day for the broader area.  
** All 2001 data are preliminary and subject to further review.  
 
San Diego Air Basin
County Site Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
San Diego Alpine-
Victoria Drive
1998 2 0 2 0.11 0.09
1999 10 0 6 0.12 0.10
2000 8 0 7 0.12 0.11
2001** 12 1 8 0.14 0.12

San Diego Escondido-
Valley Parkway
1998 0 0 0 0.09 0.08
1999 0 0 0 0.09 0.08
2000 4 0 2 0.12 0.09
2001** 2 0 0 0.11 0.08

San Diego Otay Mesa-
Paseo International
1998 0 0 0 0.07 0.06
1999 0 0 0 0.09 0.07
2000 0 0 0 0.08 0.06
2001** 0 0 0 0.08 0.07
Region* Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
San Diego Air Basin Summary 1998 4 0 3 0.11 0.10
1999 13 0 7 0.12 0.10
2000 12 0 10 0.12 0.11
2001** 16 1 8 0.14 0.12
* For the Regional summary statistics, the number of exceedance days equals the number of distinct days on which the relevant standard was exceeded at any monitoring site in the area.  If the standard was exceeded at more than one site on a given day, it only counts as one exceedance day for the broader area.  
** All 2001 data are preliminary and subject to further review.  
 
San Francisco Bay Area Air Basin
County Site Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
Alameda Livermore-
Rincon¹
1998 2 0 0 0.10 0.07
1999 2 0 0 0.12 0.08
2000 1 1 1 0.14 0.11
2001** 7 0 2 0.11 0.09

Contra Costa Concord-
2975 Treat Blvd
1998 0 0 0 0.09 0.07
1999 0 0 0 0.09 0.07
2000 1 1 1 0.14 0.09
2001** 6 1 1 0.13 0.09

Santa Clara San Jose-
935 Piedmont Road
1998 0 0 0 0.08 0.06
1999 0 0 0 0.09 0.07
2000 1 0 0 0.10 0.07
2001** 0 0 0 0.08 0.06
Region* Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
San Francisco Bay Area Air Basin
Summary
1998 3 0 0 0.10 0.08
1999 3 0 0 0.12 0.08
2000 5 2 3 0.15 0.11
2001** 12 1 6 0.13 0.10
¹ The new Livermore-Rincon site, which is a replacement for the Livermore-Old 1st Street site, started operating at the begining of 2000.
* For the Regional summary statistics, the number of exceedance days equals the number of distinct days on which the relevant standard was exceeded at any monitoring site in the area.  If the standard was exceeded at more than one site on a given day, it only counts as one exceedance day for the broader area.  
** All 2001 data are preliminary and subject to further review.  
 
San Joaquin Valley Air Basin
County Site Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
Fresno Clovis-
N Villa Avenue
1998 13 1 13 0.13 0.11
1999 15 0 15 0.12 0.10
2000 17 2 14 0.13 0.11
2001** 24 3 20 0.13 0.10

Fresno Fresno-
1st Street
1998 8 0 8 0.11 0.10
1999 13 1 17 0.13 0.10
2000 17 1 16 0.14 0.11
2001** 27 2 21 0.13 0.11

Fresno Parlier 1998 11 2 10 0.13 0.10
1999 21 3 21 0.16 0.11
2000 27 4 24 0.14 0.11
2001** 35 4 26 0.13 0.11

Kern Arvin-
Bear Mountain Blvd
1998 13 0 12 0.12 0.10
1999 26 0 24 0.12 0.11
2000 28 3 24 0.14 0.11
2001** 30 5 27 0.13 0.11

Kern Edison 1998 11 1 11 0.13 0.10
1999 18 0 15 0.11 0.10
2000 23 0 19 0.12 0.10
2001** 20 2 19 0.13 0.11
Region* Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
San Joaquin Valley Air Basin Summary 1998 22 4 19 0.13 0.11
1999 35 3 36 0.16 0.11
2000 40 7 35 0.14 0.12
2001** 46 12 43 0.13 0.12
* For the Regional summary statistics, the number of exceedance days equals the number of distinct days on which the relevant standard was exceeded at any monitoring site in the area.  If the standard was exceeded at more than one site on a given day, it only counts as one exceedance day for the broader area.  
** All 2001 data are preliminary and subject to further review.  
 
South Coast Air Quality Management District
County Site Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
Los Angeles Glendora-
Laurel
1998 11 1 7 0.17 0.12
1999 6 0 0 0.11 0.08
2000 12 6 9 0.17 0.15
2001** 27 6 17 0.18 0.14

Riverside Riverside-
Rubidoux
1998 15 2 10 0.14 0.13
1999 16 1 12 0.13 0.11
2000 15 1 11 0.14 0.11
2001** 23 2 20 0.13 0.12

San Bernardino Crestline 1998 30 14 26 0.21 0.20
1999 46 13 41 0.17 0.14
2000 43 8 31 0.18 0.15
2001** 47 13 44 0.17 0.13

San Bernardino Rim High School¹ 1998 35 12 34 0.20 0.18
1999 47 13 52 0.17 0.15
2000 47 11 42 0.19 0.16
2001** 38 11 38 0.16 0.13

San Bernardino San Bernardino-
4th Street
1998 17 7 7 0.17 0.14
1999 20 7 12 0.16 0.13
2000 19 3 9 0.15 0.13
2001** 25 6 21 0.15 0.13
Region* Year Exceedance Days Maximum
State Federal Concentrations (ppm)
1-hr 1-hr 8-hr 1-hr 8-hr
South Coast Air Quality Management District Summary 1998 33 15 28 0.21 0.20
1999 49 16 44 0.17 0.14
2000 51 13 41 0.18 0.15
2001** 59 17 50 0.18 0.14
¹ The Rim High School site is a Children Health Study site, and not a South Coast SLAMS or NAMS site.
* For the Regional summary statistics, the number of exceedance days equals the number of distinct days on which the relevant standard was exceeded at any monitoring site in the area.  If the standard was exceeded at more than one site on a given day, it only counts as one exceedance day for the broader area.  
** All 2001 data are preliminary and subject to further review.  
 
 
Please send questions or comments to:
aqdweb@cleanair.arb.ca.gov
 
This page last revised on July 10, 2001
 
----------