Belmont, Ohio Air Quality Today
AirHistory tracks long-run EPA monitoring rather than live readings, so for the live number check AirNow.gov below. As a baseline, Belmont, Ohio's most recent EPA year (2023) posted a median AQI of 31 (Good) against a 5-year median of 18 and an overall Grade of B. The dominant pollutant is Nitrogen Dioxide, which tells you which days are most likely to spike.
Check Today's Live AQI in Belmont, Ohio
AirHistory is built on 10 years of EPA Air Quality System records, so it shows you what air quality in Belmont, Ohio typically looks like — not the live reading for this exact hour. For today's real-time AQI, check AirNow.gov (the EPA's official live index) or the AirNow Fire and Smoke Map during wildfire season.
That said, the history is the best predictor of a normal day. In 2023, Belmont, Ohio posted a median AQI of 31 (Good), with 288 "Good" days and 1 days that crossed into "Unhealthy for Sensitive Groups" or worse. The dominant pollutant, Nitrogen Dioxide, is the one most likely to push today's number up — Nitrogen dioxide is emitted directly from vehicle engines, power plants, and gas appliances. It is highest near busy roads and in urban centers. Long-term NO2 exposure is linked to the development of asthma in children and to higher rates of respiratory infection.
Belmont, Ohio Air Quality Snapshot
| Air Quality Grade | B73/100 |
| 5-Year Median AQI | 18 (Good) |
| Most Recent Median AQI (2023) | 31 (Good) |
| Dominant Pollutant | Nitrogen Dioxide |
| 10-Year Trend | Worsening (+0.68 AQI/yr) |
| Unhealthy Days (last 5 yr) | 1 |
| National Rank (cleanest = #1) | #49 of 1,020 (5th cleanest percentile) |
| Ohio Rank | #3 of 40 |
What Does the B Grade Mean?
Belmont, Ohio earns a B — air quality is reliably in the safe range for most residents most of the time, with a 5-year median AQI of 18. Sensitive groups will see occasional caution days, but the typical resident will not need to change behavior based on air quality.
Belmont, Ohio's 5-year median AQI of 18 is 23 points below the national average of 41 — meaningfully cleaner than the typical U.S. metro tracked here. Within Ohio, Belmont, Ohio runs cleaner than the state average of 40 — a positive signal that local conditions (terrain, wind patterns, emission sources) are working in residents' favor.
For context within Ohio: Columbiana, Ohio currently holds the state's cleanest grade (A, AQI 12), while Butler, Ohio sits at the bottom (D, AQI 50).
What's in Belmont, Ohio's Air?
The dominant pollutant in Belmont, Ohio is Nitrogen Dioxide. Nitrogen dioxide is emitted directly from vehicle engines, power plants, and gas appliances. It is highest near busy roads and in urban centers. Long-term NO2 exposure is linked to the development of asthma in children and to higher rates of respiratory infection.
Days by Dominant Pollutant (2023)
| Pollutant | Days as Dominant | Share of Year |
|---|---|---|
| Fine Particulate Matter (PM2.5) | 239 | 68% |
| Nitrogen Dioxide | 111 | 31% |
| Coarse Particulate Matter (PM10) | 3 | 1% |
Is the Air Getting Better or Worse?
Air quality in Belmont, Ohio has been getting worse over the past decade, with median AQI climbing by roughly 0.7 points per year. That bucks the national trend of broad improvement, and most often reflects either growing wildfire smoke exposure (particularly across the West) or rising local emissions from population and freight growth.
In 2015, Belmont, Ohio posted a median AQI of 17. By 2023 that figure was 31 — a rise of 14 AQI points dirtier across 9 years of EPA records.
Year-by-Year AQI in Belmont, Ohio
| Year | Median AQI | Good Days | Unhealthy Days | Dominant Pollutant |
|---|---|---|---|---|
| 2015 | 17 | 162 | 0 | NO2 |
| 2016 | 17 | 320 | 0 | NO2 |
| 2017 | 16 | 333 | 0 | NO2 |
| 2018 | 18 | 331 | 0 | NO2 |
| 2019 | 15 | 327 | 0 | NO2 |
| 2020 | 13 | 347 | 0 | NO2 |
| 2021 | 14 | 320 | 0 | NO2 |
| 2022 | 15 | 338 | 0 | NO2 |
| 2023 | 31 | 288 | 1 | PM2.5 |
Health Context for Belmont, Ohio
Across the past five years, this area has logged just 1 days where AQI rose into the "Unhealthy for Sensitive Groups" range or worse — about 0 days per year, or roughly one every other month. That is a low count by national standards.
For most healthy adults, current air quality in this area does not require any change in behavior. People with severe asthma, COPD, or recent cardiac events should still keep an eye on daily AQI alerts, especially during wildfire season. NO2 concentrations drop quickly as you move away from traffic. Walking or biking on residential streets rather than along major arterials can cut personal exposure in half.
How This Grade Is Calculated
The AirHistory Air Quality Grade combines four signals: the 5-year median AQI (40% of the score), the 10-year trend direction (30%), the count of unhealthy days per year (20%), and the dominant pollutant type (10%). All four come directly from the EPA Air Quality System (AQS), which aggregates readings from federally certified monitors. Read the full methodology.
More about Belmont, Ohio
Belmont, Ohio has an Air Quality Grade of B (good) with a 5-year median AQI of 18. The dominant pollutant is Nitrogen Dioxide, and air quality has been worsening over the past decade.
The data source behind this answer is the EPA Air Quality System (AQS). Every figure on the page traces back to that source; the methodology page describes the inputs and the refresh cadence in full detail.
For readers turning this answer into action: cross-reference against the underlying the EPA Air Quality System (AQS) record before acting on time-sensitive decisions. The site renders the data as it was published; subsequent revisions can shift the picture, and the live federal data is always the authoritative current reference.
Source: EPA Outdoor Air Quality Data, 2026.