AIR QUALITY OR

Air Quality in Portland, OR: Good (45 AQI)

AQI 45 · Good · PM2.5 · Updated 2026-05-03

Portland's air quality is good. Air pollution poses little or no risk.

Data: EPA AirNow, FEMA National Risk Index Last verified: 2026-05-03

Average AQI

Good

AQI Category

Wildfire Risk

Mold Score

ZIP Codes

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. Portland's average AQI of 45 falls in the "Good" 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: Portland, OR

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 Portland

AQI varies across Portland's 59 ZIP codes based on proximity to pollution sources and local geography.

ZIP Code	AQI	Category	Wildfire	Mold
97201	50	Good	26	44	View report →
97202	50	Good	26	59	View report →
97203	50	Good	26	47	View report →
97204	50	Good	26	53	View report →
97205	50	Good	26	53	View report →
97206	50	Good	29	56	View report →
97207	50	Good	24	40	View report →
97208	50	Good	28	32	View report →
97209	50	Good	26	32	View report →
97210	50	Good	26	53	View report →
97211	50	Good	27	59	View report →
97212	50	Good	27	59	View report →
97213	50	Good	27	56	View report →
97214	50	Good	27	59	View report →
97215	50	Good	27	56	View report →

Showing 15 of 20 ZIP codes. View all.

Air Quality Overview

Portland, Oregon has good air quality with an average AQI of 45. This means air pollution poses little or no risk. The dominant pollutant measured is PM2.5.

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: PM2.5

PM2.5 (fine particulate matter) consists of particles smaller than 2.5 micrometers — about 30 times thinner than a human hair. These particles can penetrate deep into the lungs and enter the bloodstream.

Health effects of PM2.5 exposure:

Short-term: coughing, shortness of breath, aggravated asthma
Long-term: reduced lung function, cardiovascular disease, premature death
Most vulnerable: children, elderly, people with heart or lung disease

Common sources in urban areas: vehicle exhaust, construction dust, industrial emissions, wildfire smoke, residential wood burning.

Air Quality by ZIP Code in Portland

AQI varies across Portland's 59 ZIP codes based on proximity to pollution sources, traffic patterns, and local geography:

ZIP Code	AQI	Category	Wildfire Risk	Mold Score
97201	50	Good	26	44
97202	50	Good	26	59
97203	50	Good	26	47
97204	50	Good	26	53
97205	50	Good	26	53
97206	50	Good	29	56
97207	50	Good	24	40
97208	50	Good	28	32
97209	50	Good	26	32
97210	50	Good	26	53
97211	50	Good	27	59
97212	50	Good	27	59
97213	50	Good	27	56
97214	50	Good	27	59
97215	50	Good	27	56

Showing 15 of 59 ZIP codes. Check your specific ZIP for detailed data.

Wildfire Smoke Risk

Portland has an elevated wildfire smoke risk with an average smoke risk score of 26 (scale 0-100). There have been 1,114 fires recorded within 100 km of city ZIP codes.

Metric	Value
Avg. smoke risk score	26
Max smoke risk score	29
Fires within 100 km	1,114
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

Portland has an average mold risk score of 44 out of 100, with 11 ZIP codes in the high-risk category.

Factor	Value
Mold risk score	44/100
Average humidity	69% RH
High-risk ZIPs	11
Peak season	winter 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 good air quality (AQI 45), Portland residents can enjoy outdoor activities without significant restrictions. General tips:

Monitor AQI during wildfire season for temporary spikes
Use HEPA air purifiers indoors if you have respiratory conditions
Maintain indoor humidity between 30-50% to prevent mold

Portland vs. Nearby Oregon Cities

How Portland's air quality compares to nearby cities:

City	AQI	Category	Population
Portland	45	Good	748,643
Gen Electric	32	Good	666,200
Us Bank	50	Good	666,200
Us West	50	Good	666,200

ZIP Codes in Portland

Portland covers 59 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.

Frequently Asked Questions

Is the air safe to breathe in Portland?

Yes — Portland's average AQI is 45 (Good). Air pollution poses little or no risk for the general population.

How many unhealthy air days does Portland have?

Portland has zero recorded unhealthy air quality days, which is excellent. Air quality can still vary seasonally due to wildfire smoke, pollen, or industrial activity.

What is the AQI in Portland?

The average Air Quality Index (AQI) in Portland is 45, categorized as Good. The primary pollutant is PM2.5. AQI ranges from 0-500, where 0-50 is Good, 51-100 Moderate, 101-150 Unhealthy for Sensitive Groups, and 151+ Unhealthy.

What is the wildfire risk in Portland?

Portland has a wildfire risk score of 26 out of 100. Low wildfire risk means smoke events are uncommon, but regional fires can still temporarily affect air quality.

Is mold a concern in Portland?

Portland has a mold risk score of 44 out of 100, based on humidity, precipitation, and temperature data. Maintain good ventilation and address any water intrusion promptly to prevent mold growth.

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