Right now: Philadelphia is at 36, good.
Is the air safe to breathe in Philadelphia today?
In Philadelphia, BreatheCheck reads 36 as Go. The cutoffs: go below 101, keep it short and easy from 101 to 150, move it indoors above 150. These are our own thresholds, drawn on the EPA bands — EPA itself classifies 101–150 as Unhealthy for Sensitive Groups and does not tell you how long to stay out.
Go AQI 0–100
Normal outdoor plans. No change needed.
Short & unloaded AQI 101–150
A 20-minute dog walk, not a 2.5-hour run. Keep it brief and easy.
Don’t go AQI 151+
Move it indoors. Above 200 that becomes everyone, not just sensitive groups.
Above 200 this stops being a personal call: everyone indoors.
Duration and intensity are two separate dials
| Under 20 min | 20–60 min | Over an hour | |
|---|---|---|---|
| Easy | Go | Go | Go |
| Moderate | Go | Go | Go |
| Hard | Go | Go | Go |
Go Every combination lands the same way at this reading — a hard hour is no different from an easy twenty minutes. The two dials separate above 80.
Where people actually draw the line
All the thresholds people reported, and who reported them
- 60 Asthmatic runnerone runner’s own 156-run log
- 75–100 Daycare / schoolparents and staff in one r/toddlers thread, Aug 2025 — not a published rule
- 100 Parentcommunity-reported, escalating at 150 and 200
- 110 Runnercommunity-reported
If you’re staying in, filter the room you’re actually in
After the refinery, a highway and a river
Oil was refined where the Schuylkill meets the Delaware in South Philadelphia from 1866 onward. On June 21, 2019, a corroded pipe elbow installed in 1973 ruptured at that complex, the plant burned, and it never restarted. Investigators traced the failure to corrosion in a component more than four decades old that the operator had not identified as a risk. Whatever the site had been contributing to the city’s air stopped inside a week, which leaves Philadelphia with something few metros have: a dated line across its own pollution record that residents can remember.
What remains is mobile and linear. The Delaware waterfront from Port Richmond and Bridesburg down past the port terminals is industrial land wrapped around I-95, and research on the city has found worse air and higher asthma prevalence in the neighborhoods along that corridor than in those further from it. The ground offers no help. It is low, flat and tidal, with nothing to lift a plume or channel it away.
Ozone is the standing regulatory problem, and it is not solely Philadelphia’s doing. The five-county Pennsylvania area carries a nonattainment designation for the current ozone standard and was rated Severe under an earlier one. Pennsylvania sits inside the Ozone Transport Region that Congress drew in 1990, precisely because summer southwesterly flow carries the ingredients up this corridor from states upwind of it.
Where this number sits
Of the 121 US metros reporting to us right now, Philadelphia is number 76 and number 2 of the 2 we track in Pennsylvania. The pollutant driving it today is O3.
Nearby metros we also measure, and what they read at the same hour:
- Wilmington, DE — 25 miles away, AQI 31
- Dover, DE — 58 miles away, AQI 37
- Newark, NJ — 75 miles away, AQI 24
- Jersey City, NJ — 78 miles away, AQI 24
Where this reading comes from
AirNow’s Philadelphia reporting area, about 0.5 miles from the metro centre.
What has air quality in Philadelphia actually been?
0 of the 30 days we have recorded so far went above AQI 100.
| Date | Daily max AQI | EPA band | Hours read |
|---|---|---|---|
| 52 | Moderate | 22 | |
| 52 | Moderate | 23 | |
| 58 | Moderate | 23 | |
| 55 | Moderate | 23 | |
| 56 | Moderate | 23 | |
| 55 | Moderate | 22 | |
| 57 | Moderate | 23 | |
| 39 | Good | 23 | |
| 39 | Good | 23 | |
| 52 | Moderate | 23 | |
| 59 | Moderate | 23 | |
| 53 | Moderate | 24 | |
| 71 | Moderate | 23 | |
| 77 | Moderate | 23 | |
| 60 | Moderate | 23 | |
| 62 | Moderate | 23 | |
| 55 | Moderate | 23 | |
| 55 | Moderate | 23 | |
| 56 | Moderate | 23 | |
| 61 | Moderate | 23 | |
| 59 | Moderate | 23 | |
| 61 | Moderate | 24 | |
| 55 | Moderate | 23 | |
| 58 | Moderate | 23 | |
| 57 | Moderate | 23 | |
| 70 | Moderate | 23 | |
| 61 | Moderate | 23 | |
| 71 | Moderate | 23 | |
| 63 | Moderate | 26 | |
| 60 | Moderate | 7 — partial day |
Questions about Philadelphia
What is the air quality in Philadelphia right now?
Which monitor does this number come from?
How does Philadelphia compare with metros nearby?
Does this include pollen?
Put this number in context
Updated