Data: EPA AirNow, FEMA National Risk Index Last verified:

What is AQI?

The Air Quality Index (AQI) is a standardized scale from 0 to 500 that measures air pollution levels. 0-50 is "Good," 51-100 is "Moderate," 101-150 is "Unhealthy for Sensitive Groups," and above 150 is "Unhealthy" for everyone. AQI tracks five major pollutants: ground-level ozone, particulate matter (PM2.5 and PM10), carbon monoxide, sulfur dioxide, and nitrogen dioxide. San Bernardino's average AQI of 118 falls in the "USG" range.

How do wildfires affect air quality?

Wildfire smoke contains fine particulate matter (PM2.5) that can travel hundreds of miles and dramatically spike AQI readings. During fire season, even cities far from active fires can experience unhealthy air. HEPA air purifiers (rated for PM2.5) are the most effective indoor protection. Check AirNow.gov for real-time conditions during fire season.

Air Quality Map: San Bernardino, CA

Each dot represents a ZIP code. Color indicates AQI level. Tap a dot for details.

Good (0-50) Moderate (51-100) USG (101-150) Unhealthy (151+)

Air Quality by ZIP Code in San Bernardino

AQI varies across San Bernardino's 18 ZIP codes based on proximity to pollution sources and local geography.

ZIP Code	AQI	Category	Wildfire	Mold
92407	128	USG	80	35	View report →
92414	128	USG	80	12	View report →
92412	119	USG	80	12	View report →
92401	117	USG	80	29	View report →
92402	117	USG	80	13	View report →
92403	117	USG	80	12	View report →
92404	117	USG	80	41	View report →
92405	117	USG	80	36	View report →
92406	117	USG	80	12	View report →
92408	117	USG	80	28	View report →
92410	117	USG	80	31	View report →
92411	117	USG	80	48	View report →
92413	117	USG	80	12	View report →
92415	117	USG	80	10	View report →
92418	117	USG	80	12	View report →

Showing 15 of 18 ZIP codes. View all.

Air Quality Overview

San Bernardino, California has air quality rated Unhealthy for Sensitive Groups with an average AQI of 118. People with respiratory conditions, children, and older adults may experience health effects. The dominant pollutant is Ozone.

The Air Quality Index (AQI) is an EPA-standardized scale from 0 to 500. Values below 50 are "Good," 51-100 "Moderate," 101-150 "Unhealthy for Sensitive Groups," 151-200 "Unhealthy," 201-300 "Very Unhealthy," and above 300 "Hazardous."

Dominant Pollutant: Ozone

Ground-level ozone forms when pollutants from cars, power plants, and industrial facilities react with sunlight. Unlike stratospheric ozone, ground-level ozone is harmful to breathe.

Health effects of ozone exposure:

• Irritation of the respiratory system
• Reduced lung function
• Aggravation of asthma and chronic lung diseases
• Increased susceptibility to respiratory infections

Peak times: Ozone levels are typically highest on hot, sunny afternoons. Exercise outdoors in the morning when levels are lower.

Air Quality by ZIP Code in San Bernardino

AQI varies across San Bernardino's 18 ZIP codes based on proximity to pollution sources, traffic patterns, and local geography:

Showing 15 of 18 ZIP codes. Check your specific ZIP for detailed data.

Wildfire Smoke Risk

San Bernardino has an elevated wildfire smoke risk with an average smoke risk score of 80 (scale 0-100). There have been 753 fires recorded within 100 km of city ZIP codes.

Metric	Value
Avg. smoke risk score	80
Max smoke risk score	80
Fires within 100 km	753
High-risk ZIP codes	18

Wildfire smoke contains PM2.5, carbon monoxide, and volatile organic compounds. Even short-term exposure can trigger asthma attacks and respiratory distress.

Indoor Mold Risk

San Bernardino has an average mold risk score of 21 out of 100.

Factor	Value
Mold risk score	21/100
Average humidity	54% RH
High-risk ZIPs	0
Peak season	balanced

Mold risk is influenced by humidity levels, housing age (older homes have more moisture issues), flood history, and water infrastructure quality. Indoor humidity above 60% creates favorable conditions for mold growth.

Signs of mold problems: musty odors, visible growth on walls or ceilings, worsening allergies indoors, condensation on windows. Professional mold testing ($300-$600) can identify hidden issues.

Health Recommendations

With USG-level air quality (AQI 118), sensitive groups should limit outdoor exposure:

• Sensitive groups: avoid prolonged outdoor exertion
• General public: reduce prolonged or heavy outdoor exertion
• Keep windows and doors closed
• Run HEPA air purifiers continuously
• Wear N95 masks outdoors if prolonged exposure is unavoidable

San Bernardino vs. Nearby California Cities

How San Bernardino's air quality compares to nearby cities:

ZIP Codes in San Bernardino

San Bernardino covers 18 ZIP codes. Air quality can vary by neighborhood based on proximity to highways, industrial areas, and green spaces. Check your specific ZIP code for localized data.

Data Sources

• Air quality: EPA AirNow - real-time and historical AQI data
• Wildfire risk: FEMA National Risk Index
• Mold risk: Derived from EPA, FEMA, Census ACS (humidity, housing age, flood history)
• Monthly AQI: EPA Air Quality Statistics

Source reporting periods vary. See each cited source for its publication schedule.