Ozone in Modesto, CA
Real-time Ground-level Ozone monitoring and health recommendations
Current Ozone Levels
Overall AQI
About Ground-level Ozone
A harmful gas created by chemical reactions between pollutants in sunlight.
Measured in ppb
Health Impact
Air quality is acceptable; however, for some pollutants there may be a moderate health concern for a very small number of people who are unusually sensitive to air pollution.
Active children and adults, and people with respiratory disease, such as asthma, should limit prolonged outdoor exertion.
What Is a Safe Level of Ozone?
By the EPA Air Quality Index, ground-level ozone is Good — safe for everyone up to 54 ppb (AQI 0–50). From 54 to 70 ppb is Moderate (AQI 51–100): acceptable for most people, though unusually sensitive individuals may notice symptoms. Above 70 ppb the air turns Unhealthy for Sensitive Groups and EPA health guidance applies.
Modesto is currently at AQI 58 (≈57 ppb, estimated) for Ozone — in the Moderate range, which is acceptable for most people but worth watching if you're in a sensitive group.
Thresholds are the official EPA AQI category breakpoints for ground-level ozone (8-hour standard). The current concentration is estimated from the measured AQI sub-index; the exact value within a band is not recoverable from the index alone.
Sources of Ozone
• Chemical reactions between NOx and VOCs in sunlight
• Vehicle emissions
• Industrial facilities
• Gasoline vapors and solvents
Other Pollutants
Full Air Quality Report
View all pollutants and comprehensive air quality data for Modesto.
View Full ReportReduce Indoor Ozone in Modesto
Today's main pollutant in Modesto is ground-level ozone (AQI 59). Important: standard HEPA filters do NOT remove ozone — only a purifier with a substantial activated-carbon bed adsorbs it. The biggest wins are cutting indoor sources (gas appliances, certain "ionizer" purifiers) and ventilating when outdoor ozone is low (early morning). A high-carbon unit helps with the gases and VOCs that linger indoors.
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Reduce Indoor Ozone in Modesto
Today's main pollutant in Modesto is ground-level ozone (AQI 59). Important: standard HEPA filters do NOT remove ozone — only a purifier with a substantial activated-carbon bed adsorbs it. The biggest wins are cutting indoor sources (gas appliances, certain "ionizer" purifiers) and ventilating when outdoor ozone is low (early morning). A high-carbon unit helps with the gases and VOCs that linger indoors.
Compare activated-carbon purifiers (for gases & ozone):
Prices are approximate and subject to change. As an Amazon Associate, we earn from qualifying purchases at no extra cost to you.
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