Air Quality in Bangor, Maine — Live

Live readings from PurpleAir sensors across Bangor — with free alerts if wildfire smoke or wood smoke moves in.

Live Bangor AQI from nearby PurpleAir sensors loads when this page opens in a browser, along with a live sensor map covering Bangor and Brewer, Hampden, Orono, Old Town.

Bangor's air is about as clean as it gets in America. Penobscot County is the only metro area in the country to land on all three of the American Lung Association's 2026 "State of the Air" Cleanest Cities lists — for ozone, for short-term particle pollution, and for year-round particle pollution — with straight A grades and effectively zero unhealthy air days most years. The exceptions are real but occasional: wood smoke settling into neighborhoods on cold, still winter nights, and the rare summer when Canadian wildfire smoke drifts far enough south to reach the Penobscot valley.

Canairy watches the sensors around your home, your kids' school, and everywhere else you care about, and tells you in plain English when the air changes enough to matter.

Bangor is the only US metro on every Cleanest Cities list

In the American Lung Association's 2026 State of the Air report, the Bangor metro area — Penobscot County — was the only metro area in the entire country to make all three of the group's Cleanest Cities rankings: cleanest for ozone (its ninth straight year with a perfect grade), cleanest for short-term particle pollution (its seventeenth straight year), and among the ten cleanest nationally for year-round particle pollution. Both the ozone and short-term particle grades came back a straight A, with zero high-pollution days over the report's 2022-2024 monitoring window.

That is not a fluke of one good year. The same report gives Maine's other population centers a much rougher grade: the Portland-Lewiston-South Portland metro and Cumberland and York Counties all scored a C for ozone, and Cumberland County posted the worst year-round particle pollution grade in the state. Bangor sharing a state with cities that grade out that differently is itself the local story — the air here is not generically "New England air," it is specifically some of the best-monitored, cleanest air of any American city its size.

Why the coast struggles with ozone and Bangor mostly doesn't

Maine's own Department of Environmental Protection explains the coastal problem plainly: ozone and the pollutants that form it get carried out of the New York and Boston corridor, ride a cooling sea breeze onto the Gulf of Maine, and turn back toward shore, concentrating in a shallow layer right along the coastline and in the river valleys that drain to it. Peak ozone timing then rolls eastward through the afternoon and evening as that breeze pushes up the coast toward Mount Desert Island.

Bangor sits about 30 miles inland, up the tidal reach of the Penobscot River, away from that shoreline conveyor belt. Maine DEP's own material notes that inland vegetation scrubs ozone out of the air as it moves away from the coast, and Bangor's smaller traffic and industrial base than the southern Maine cities gives it less to add locally in the first place. That combination of distance from the transport corridor and modest local emissions is the practical reason a straight-A city and a string of C-grade counties can sit in the same state.

The two ways a clean-air city still gets a bad day

Maine is the second-most wood-heated state in the country — about 8.8% of homes use wood as their primary heat source, behind only Vermont's 12.5% — and that's a familiar sight in Bangor, across the river in Brewer, and in the rural towns around Penobscot County. On a cold, calm January or February night, smoke from stoves and fireplaces settles low over a neighborhood in a way the county's official monitor, built to track the broader average, doesn't fully capture at the block level.

The other exception showed up in 2023. That June, rain shielded most of Maine while smoke from Quebec fires gave southern New England some of the worst air quality it has seen in recorded history — Bangor mostly caught a break. By September, a denser plume from wildfires burning in Alberta reached Maine anyway, and the DEP issued an air-quality alert specifically for Northern Maine as particle pollution climbed into the Unhealthy for Sensitive Groups range. It doesn't happen most years, but a city with this good a track record is exactly the kind of place where nobody has a habit of checking — until the one week they need to.

Bangor air quality FAQ

What is the air quality in Bangor right now?

This page shows the current AQI for Bangor, calculated from PurpleAir sensors across the city and updated continuously. The map below shows every live sensor, so you can check the reading closest to your own neighborhood.

Why does Bangor have some of the cleanest air in the country?

In the American Lung Association's 2026 State of the Air report, the Bangor metro area (Penobscot County) was the only metro area in the nation to earn a spot on all three Cleanest Cities lists — ozone, short-term particle pollution, and year-round particle pollution — with straight A grades. Sitting roughly 30 miles inland up the Penobscot River keeps Bangor away from the sea-breeze corridor that concentrates ozone transported up the coast from Boston and New York, which is part of why coastal Maine cities like Portland grade out worse.

Does Canadian wildfire smoke ever reach Bangor?

Yes, though it's rare. In June 2023, rain shielded most of Maine while a Quebec smoke plume gave southern New England some of its worst air quality on record. By September 2023 a denser plume from fires burning in Alberta reached Maine, and the DEP issued an air-quality alert for Northern Maine as particle pollution climbed into the Unhealthy for Sensitive Groups range. It doesn't happen every summer, but when it does, it's worth checking your number instead of guessing from the color of the sky.

What AQI level is unhealthy?

Under the US EPA scale, AQI 0-50 is Good and 51-100 is Moderate. From 101 the air is Unhealthy for Sensitive Groups - kids, older adults, and people with asthma or heart conditions - and above 150 it's Unhealthy for everyone. Canairy translates these numbers into a plain-English verdict, like whether to close the windows or move a workout indoors.

Where does Canairy's Bangor data come from?

Readings come from PurpleAir's network of laser particle sensors across Bangor and nearby Penobscot County towns like Brewer and Orono, cross-referenced with government monitors and the Google Air Quality API. You can see every sensor behind your numbers on the live map - there's no black box.

Is Canairy free?

Yes. The Canairy app is free to download and includes live air quality for all your saved places, plain-English verdicts, and free push alerts when the air crosses your threshold. A paid plan adds extras like SMS text alerts.

Get Canairy free on Google Play.