# Philadelphia, PA Air Quality Index (AQI) Today > Source: https://breathecheck.com/air-quality/us/pennsylvania/philadelphia/ > Live AQI for Philadelphia, PA with a plain verdict — go, short and unloaded, or don't go — plus the monitor behind it and our own hourly record. # Philadelphia, PA Air Quality Index (AQI) Today Readings collected automatically every hour; text written and checked by BreatheCheck Editorial . How this page is made → 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 runner one runner’s own 156-run log - 75–100 Daycare / school parents and staff in one r/toddlers thread, Aug 2025 — not a published rule - 100 Parent community-reported, escalating at 150 and 200 - 110 Runner community-reported EPA classifies 101–150 as Unhealthy for Sensitive Groups. That is an attributed classification, not a verdict on your lungs specifically. If you’re staying in, filter the room you’re actually in A portable HEPA unit or a Corsi-Rosenthal box — one builder put theirs at about $130 for a 12×14 bedroom. We don’t default to a MERV-13 swap in whole-house HVAC: it can restrict airflow, and the safe version needs a static-pressure check first. Dominant pollutant O3 UV index 0.3 low · modelled UV hour by hour in Philadelphia → Days above AQI 100 0 of 30 days we have recorded The record, day by day → ### 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 Why a metro a short drive away reads differently → 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? Daily maximum, our own readings. 30 days since 2026-08-16; nothing back-filled. Why we keep our own → 0 of the 30 days we have recorded so far went above AQI 100. | Date | Daily max AQI | EPA band | Hours read | | 2026-09-14 | 52 | Moderate | 22 | | 2026-09-13 | 52 | Moderate | 23 | | 2026-09-12 | 58 | Moderate | 23 | | 2026-09-11 | 55 | Moderate | 23 | | 2026-09-10 | 56 | Moderate | 23 | | 2026-09-09 | 55 | Moderate | 22 | | 2026-09-08 | 57 | Moderate | 23 | | 2026-09-07 | 39 | Good | 23 | | 2026-09-06 | 39 | Good | 23 | | 2026-09-05 | 52 | Moderate | 23 | | 2026-09-04 | 59 | Moderate | 23 | | 2026-09-03 | 53 | Moderate | 24 | | 2026-09-02 | 71 | Moderate | 23 | | 2026-09-01 | 77 | Moderate | 23 | | 2026-08-31 | 60 | Moderate | 23 | | 2026-08-30 | 62 | Moderate | 23 | | 2026-08-29 | 55 | Moderate | 23 | | 2026-08-28 | 55 | Moderate | 23 | | 2026-08-27 | 56 | Moderate | 23 | | 2026-08-26 | 61 | Moderate | 23 | | 2026-08-25 | 59 | Moderate | 23 | | 2026-08-24 | 61 | Moderate | 24 | | 2026-08-23 | 55 | Moderate | 23 | | 2026-08-22 | 58 | Moderate | 23 | | 2026-08-21 | 57 | Moderate | 23 | | 2026-08-20 | 70 | Moderate | 23 | | 2026-08-19 | 61 | Moderate | 23 | | 2026-08-18 | 71 | Moderate | 23 | | 2026-08-17 | 63 | Moderate | 26 | | 2026-08-16 | 60 | Moderate | 7 — partial day | ## Questions about Philadelphia **What is the air quality in Philadelphia right now?** AQI 36 — Good. That is number 76 of the 121 US metros reporting to us at this hour. **Which monitor does this number come from?** Philadelphia, about 0.5 miles from the metro centre. One instrument reports for the whole metro, so the side farthest from it is the least well described. **How does Philadelphia compare with metros nearby?** At this hour: Wilmington 31, Dover 37, Newark 24, Jersey City 24. Readings that close together suggest one airshed rather than local sources. **Does this include pollen?** No. The AQI covers PM2.5 , PM10 , ozone, NO₂, SO₂ and CO. A high-pollen day can read clean here and still put someone in bed. What the number means, band by band → · UV in Philadelphia → · Why apps disagree → ## Put this number in context On this page Alert me when Philadelphia turns One email when it crosses your threshold. Updated 14 Sep 2026, 22:12 UTC