Air Quality in Portsmouth, VA: Moderate (55 AQI)
AQI 55 · Moderate · Ozone · Updated 2026-05-03
Portsmouth's air quality is moderate. Unusually sensitive people should consider reducing prolonged outdoor exertion.
Data: EPA AirNow, FEMA National Risk Index Last verified: 2026-05-03
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. Portsmouth's average AQI of 55 falls in the "Moderate" range.
Air Quality Map: Portsmouth, VA
Each dot represents a ZIP code. Color indicates AQI level. Tap a dot for details.
Air Quality by ZIP Code in Portsmouth
AQI varies across Portsmouth's 8 ZIP codes based on proximity to pollution sources and local geography.
| ZIP Code | AQI | Category | Wildfire | Mold | |
|---|---|---|---|---|---|
| 23701 | 55 | Moderate | 7 | 60 | View report → |
| 23702 | 55 | Moderate | 7 | 63 | View report → |
| 23703 | 55 | Moderate | 7 | 56 | View report → |
| 23704 | 55 | Moderate | 7 | 65 | View report → |
| 23705 | 55 | Moderate | 7 | 33 | View report → |
| 23707 | 55 | Moderate | 7 | 63 | View report → |
| 23708 | 55 | Moderate | 7 | 51 | View report → |
| 23709 | 55 | Moderate | 7 | 33 | View report → |
Air Quality Overview
Portsmouth, Virginia has moderate air quality with an average AQI of 55. 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 Portsmouth
AQI varies across Portsmouth's 8 ZIP codes based on proximity to pollution sources, traffic patterns, and local geography:
| ZIP Code | AQI | Category | Wildfire Risk | Mold Score |
|---|---|---|---|---|
| 23701 | 55 | Moderate | 7 | 60 |
| 23702 | 55 | Moderate | 7 | 63 |
| 23703 | 55 | Moderate | 7 | 56 |
| 23704 | 55 | Moderate | 7 | 65 |
| 23705 | 55 | Moderate | 7 | 33 |
| 23707 | 55 | Moderate | 7 | 63 |
| 23708 | 55 | Moderate | 7 | 51 |
| 23709 | 55 | Moderate | 7 | 33 |
Wildfire Smoke Risk
Portsmouth has a low wildfire smoke risk with an average smoke risk score of 7 (scale 0-100). However, smoke from distant wildfires can temporarily degrade air quality even in low-risk areas.
| Metric | Value |
|---|---|
| Avg. smoke risk score | 7 |
| Max smoke risk score | 7 |
| Fires within 100 km | 0 |
| 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
Portsmouth has an average mold risk score of 53 out of 100, with 5 ZIP codes in the high-risk category.
| Factor | Value |
|---|---|
| Mold risk score | 53/100 |
| Average humidity | 69% RH |
| High-risk ZIPs | 5 |
| 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 55), 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
Portsmouth vs. Nearby Virginia Cities
How Portsmouth's air quality compares to nearby cities:
| City | AQI | Category | Population |
|---|---|---|---|
| Portsmouth | 55 | Moderate | 17,000 |
| Fort Eustis | 52 | Moderate | 16,900 |
| Belspring | 51 | Moderate | 17,420 |
| New River | 51 | Moderate | 17,420 |
ZIP Codes in Portsmouth
Portsmouth covers 8 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.