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Primary air pollutant in the Portola Valley area:
PM2.5 - 55 Moderate
If you are unusually sensitive to particle pollution, consider reducing your activity level or shorten the amount of time you are active outdoors.
Other Pollutants:
OZONE - 1 Good
Primary Pollutant: PM2.5 - 50 Good
Primary Pollutant: PM2.5 - 55 Moderate
Primary Pollutant: PM2.5 - 0 Moderate
Primary Pollutant: PM2.5 - 0 Moderate
Primary Pollutant: PM2.5 - 0 Moderate
Primary Pollutant: PM2.5 - 0 Moderate