ARB Logo California Map with Basin Highlighted
Basin by Basin Comparison of 1995 Ozone Data
Basin Name Days Standard Exceeded Ozone Concentrations in ppm
1 hour 8 hour
State
1hr
Federal
1hr
Federal
8hr
Max
1hr
3 Year
4th High*
EPDC*
Max
8hr
3 Year Avg
4th High*
Great Basin Valleys 2 0 2 0.11 0.10 0.097 0.101 0.079
Lake County 0 0 0 0.07 0.08 0.082 0.063 0.061
Lake Tahoe 0 0 1 0.09 0.09 0.084 0.089 0.070
Mojave Desert 115 53 105 0.24 0.19   0.170 0.133
Mountain Counties 49 3 47 0.15 0.12 0.131 0.113 0.099
North Central Coast 8 1 3 0.14 0.10 0.106 0.102 0.081
North Coast 1 0 1 0.10 0.09 0.090 0.090 0.069
Northeast Plateau 0 0 0 0.07 0.07 0.074 0.062 0.057
Sacramento Valley 50 11 40 0.16 0.15 0.149 0.128 0.106
Salton Sea 124 33 79 0.23 0.18 0.163 0.132 0.110
San Diego 96 12 48 0.16 0.15 0.148 0.122 0.108
San Francisco B. A. 28 11 18 0.16 0.14 0.135 0.115 0.087
San Joaquin Valley 124 44 109 0.17 0.17 0.163 0.134 0.119
South Central Coast 95 25 70 0.17 0.16 0.162 0.144 0.117
South Coast 153 98 120 0.26 0.25 0.249 0.203 0.165
* The 3 year 4th high, 3 year average 4th high, and Expected Peak Day Concentration (EPDC) are calculated based on data for 3 successive years, listed by the last year of the three year period.  The EPDC represents the ozone concentration expected to occur once per year.
   

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This page last revised on March 26, 1999

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