Data: EPA AirNow, FEMA National Risk Index Last verified: 2026-07-18

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. Philadelphia's average AQI of 77 falls in the "Moderate" range.

Air Quality Map: Philadelphia, PA

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 Philadelphia

AQI varies across Philadelphia's 87 ZIP codes based on proximity to pollution sources and local geography.

ZIP Code	AQI	Category	Wildfire	Mold
19019	77	Moderate	20	51	View report →
19092	77	Moderate	20	51	View report →
19093	77	Moderate	20	51	View report →
19099	77	Moderate	20	51	View report →
19101	77	Moderate	20	41	View report →
19102	77	Moderate	19	50	View report →
19103	77	Moderate	20	66	View report →
19104	77	Moderate	20	60	View report →
19105	77	Moderate	19	41	View report →
19106	77	Moderate	19	54	View report →
19107	77	Moderate	19	60	View report →
19108	77	Moderate	20	68	View report →
19109	77	Moderate	19	51	View report →
19110	77	Moderate	19	41	View report →
19111	77	Moderate	20	57	View report →

Showing 15 of 20 ZIP codes. View all.

Air Quality Overview

Philadelphia, Pennsylvania has moderate air quality with an average AQI of 77. Air quality is acceptable, though some pollutants may be a concern for a small number of people who are unusually sensitive to air pollution. 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 Philadelphia

AQI varies across Philadelphia's 87 ZIP codes based on proximity to pollution sources, traffic patterns, and local geography:

Showing 15 of 87 ZIP codes. Check your specific ZIP for detailed data.

Wildfire Smoke Risk

Philadelphia has an elevated wildfire smoke risk with an average smoke risk score of 19 (scale 0-100). There have been 927 fires recorded within 100 km of city ZIP codes.

Metric	Value
Avg. smoke risk score	19
Max smoke risk score	20
Fires within 100 km	927
High-risk ZIP codes	0

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

Philadelphia has an average mold risk score of 55 out of 100, with 42 ZIP codes in the high-risk category.

Factor	Value
Mold risk score	55/100
Average humidity	68% RH
High-risk ZIPs	42
Peak season	summer high

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 moderate air quality (AQI 77), most people can be active outdoors. Sensitive groups should take precautions:

• Sensitive groups (asthma, COPD, heart disease): consider reducing prolonged outdoor exertion
• Keep windows closed on high-pollution days
• Use a HEPA air purifier in main living areas
• Check AirNow.gov before outdoor exercise

Philadelphia vs. Nearby Pennsylvania Cities

How Philadelphia's air quality compares to nearby cities:

ZIP Codes in Philadelphia

Philadelphia covers 87 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

Updated daily.