BreatheErie helps people in and around Erie, Pennsylvania understand the air they breathe — and act on it. It’s free, has no ads, and isn’t selling anything.
The name is breathe plus Erie — Breathe Erie. It’s about the city and the lake air, not anything eerie.
How Erie actually rates
Worth being straight about this, because plenty of air quality sites lead with alarm: Erie’s air is decent.
The American Lung Association’s State of the Air 2026 report graded every county in the country using EPA monitoring data from 2022 through 2024. Erie County came out:
One important caveat on these grades: the most recent data in the 2026 report is from 2024 — already two years old by the time you read it. The world has been warmer, drier, and more fire-prone every year since. The 2026 report is actually more concerning than the 2025 edition, which used 2021–2023 data, and the trend is consistently worsening. What Erie grades as a C today may look different in next year’s edition when 2025’s smoke-heavy season gets factored in. Annual averages are the rearview mirror. This site is the windshield.
For the most current full-year data available anywhere right now, the EPA published Air Quality Statistics by County, 2025 on June 2, 2026 — actual 2025 calendar-year monitoring data from their AQS database. This is more recent than anything the ALA has published. Erie Vital Signs also tracks Erie Vital Signs livability data (find Air Quality in the indicators) — good days peaked at 297 in 2020 and dropped to 240 by 2023, a trend that predates the ALA’s grading cycle by a year.
| Measure | Grade | Detail |
|---|---|---|
| Ozone days | C | 3 orange days, none worse. 135th of 226 metros. |
| Short-term particle spikes | C | 1 orange day, 3 red. 101st of 224 metros. |
| Year-round particles | Pass | Design value 6.8. The failing line is 9.1. |
For comparison, the Pittsburgh and Philadelphia metros both took failing grades across the board. We are not them.
So why does this site exist?
Look at that middle row again. Erie passed the year-round particle test comfortably — and still had three red days. Red means unhealthy for everyone, not just sensitive groups.
That’s the whole problem in one line. An annual average can be excellent while individual days are dangerous. Those red days were wildfire smoke; the 2023 Canadian smoke episode that turned the eastern sky orange is still sitting in those numbers. A grade covering three years cannot tell you whether to take your kid to the park on Thursday.
As the Lung Association’s Kevin Stewart put it when the report came out: “Lungs don’t care where the air pollution is coming from.” Smoke from a fire two thousand miles away does the same damage as smoke from down the street.
So this site tracks the days, not the years.
What you’re seeing on the home page
The big number
That’s the official EPA Air Quality Index for Erie, pulled live from AirNow. Two things about it are worth understanding.
The AQI is the worst pollutant, not the average of them. EPA measures several — fine particles, ozone, and others — and reports whichever is highest. So the headline number might be driven by ozone on a hot afternoon and by smoke on a hazy one. We print which pollutant is responsible underneath, because the right response is different for each. A HEPA filter does nothing for ozone.
It’s an hourly average, and it lags. AirNow smooths readings using an algorithm called NowCast. That’s deliberate and sensible for a daily health index, but during a fast-moving smoke event the official number can sit well below what you’re breathing right now. This is why we also point you at the live sensor maps below it.
PurpleAir PM2.5
PM2.5 means particles 2.5 micrometers across or smaller — roughly thirty times thinner than a human hair. Small enough to slip past your body’s defenses and reach deep into the lungs; the smallest cross into the bloodstream. It comes from anything burning: engines, wood stoves, industry, wildfires.
PurpleAir is a network of low-cost sensors on people’s porches. Compared to the official monitor, it is more current and more local, but less accurate. Any single sensor might sit next to a barbecue or under a leaky eave. The official instrument is better; it’s just slower and further away. Use PurpleAir as an early warning, AirNow as the official record. When they disagree sharply, something is changing fast — and that gap is itself information.
Volatile Organic Compounds (VOCs)
Gases from paint, solvents, cleaning products, fuel, new furniture — and plenty of natural sources too. Some are harmless, some are irritants, a few are carcinogens.
PurpleAir labels this layer experimental, and we keep that label. It reports in a proprietary Bosch index rather than a regulated standard, and PurpleAir deliberately assigns no health categories to it — the same reading can mean very different things depending on the source. Treat it as one signal, not a verdict. Watch trends rather than spikes; a passing truck can move it briefly.
Fire & Smoke Map
Run jointly by the EPA and US Forest Service. Shows active fires, official monitors, and satellite-traced smoke plumes together.
One thing matters more than anything else here: a plume overhead does not mean smoke at ground level. Those polygons are drawn from satellite imagery and often show smoke passing thousands of feet above you. In our part of the country especially, research has found surface pollution inside plume areas is frequently low. Cross-check the plume against the monitor dots underneath it. The dots are measurements; the plume is a tracing.
For where smoke is headed next, see How to Read the Smoke Forecast.
Living on the lake
Many of us live within a mile of the shoreline. The lake runs our weather — lake-effect snow in winter, humidity through spring, summer and fall.
You’ll read in places that humid air makes fine particles swell and therefore more damaging. The swelling part is real — it’s called hygroscopic growth. The “therefore” is not. Modeling studies find that as these particles absorb water and grow, deposition in the airway actually decreases somewhat. And your airways sit at about 99.5% humidity no matter what your living room is doing, so particles grow the instant you inhale them regardless. Room humidity is not the lever it sounds like.
Keeping indoor humidity between 30 and 50% is still worth doing. Above 60% is independently irritating to airways, and it feeds mold and dust mites. Just don’t do it expecting protection from smoke.
Coming next
- Protect Yourself — a fuller treatment of HEPA filters, which masks actually work, and building a daily habit around checking conditions.
- The Science — what PM2.5 and ozone actually do in the body, and why they need different responses.
- Stories — what smoke days are like for people here who feel them first.
About this site. BreatheErie is built independently and is not affiliated with the EPA, NOAA, the US Forest Service, PurpleAir, Pivotal Weather, or the American Lung Association. We display their public maps and cite their research; the interpretation is ours, and so is any error in it. Grades and figures above come from the American Lung Association’s State of the Air 2026 report, covering 2022–2024. Nothing here is medical advice — if you have respiratory or cardiovascular concerns, talk to your doctor.