EnviroNearby

Baker County, Oregon air quality history

Daily Air Quality Index summaries from EPA monitors in Baker, Oregon, 2005–2025.

83%
Good days in 2025
29
Median daily AQI, 2025
0
Days above 100 in 2025
365
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Baker, Oregon on 365 days. 304 of those days (83%) were in the Good range, and the median daily AQI was 29. That median is about the same as the typical monitored county in Oregon (median 29 across 21 counties), and lower than the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 365 days. Across the years with fuller monitoring, the share of Good days rose: an average of 74% in 2005–2007 versus 81% in 2023–2025.

How the days broke down each year

Each bar is one year. The colored segments show the share of monitored days that fell in each AQI category.

Share of monitored days in each AQI category, by year0%25%50%75%100%2005: Good 217 of 274 days2005: Moderate 56 of 274 days2005: Unhealthy for Sensitive Groups 1 of 274 days20052006: Good 253 of 356 days2006: Moderate 101 of 356 days2006: Unhealthy for Sensitive Groups 2 of 356 days2007: Good 255 of 363 days2007: Moderate 108 of 363 days20072008: Good 236 of 366 days2008: Moderate 129 of 366 days2008: Unhealthy for Sensitive Groups 1 of 366 days2009: Good 244 of 361 days2009: Moderate 117 of 361 days20092010: Good 267 of 356 days2010: Moderate 89 of 356 days2011: Good 254 of 352 days2011: Moderate 98 of 352 days20112012: Good 275 of 366 days2012: Moderate 89 of 366 days2012: Unhealthy for Sensitive Groups 2 of 366 days2013: Good 223 of 365 days2013: Moderate 142 of 365 days20132014: Good 284 of 365 days2014: Moderate 81 of 365 days2015: Good 285 of 365 days2015: Moderate 70 of 365 days2015: Unhealthy for Sensitive Groups 8 of 365 days2015: Unhealthy 2 of 365 days20152016: Good 303 of 362 days2016: Moderate 59 of 362 days2017: Good 273 of 365 days2017: Moderate 86 of 365 days2017: Unhealthy for Sensitive Groups 3 of 365 days2017: Unhealthy 3 of 365 days20172018: Good 273 of 347 days2018: Moderate 72 of 347 days2018: Unhealthy for Sensitive Groups 1 of 347 days2018: Unhealthy 1 of 347 days2019: Good 293 of 360 days2019: Moderate 67 of 360 days20192020: Good 282 of 366 days2020: Moderate 77 of 366 days2020: Unhealthy for Sensitive Groups 2 of 366 days2020: Unhealthy 3 of 366 days2020: Very Unhealthy 2 of 366 days2021: Good 271 of 364 days2021: Moderate 88 of 364 days2021: Unhealthy for Sensitive Groups 1 of 364 days2021: Unhealthy 4 of 364 days20212022: Good 283 of 365 days2022: Moderate 79 of 365 days2022: Unhealthy for Sensitive Groups 3 of 365 days2023: Good 301 of 363 days2023: Moderate 62 of 363 days20232024: Good 279 of 366 days2024: Moderate 84 of 366 days2024: Unhealthy for Sensitive Groups 1 of 366 days2024: Unhealthy 2 of 366 days2025: Good 304 of 365 days2025: Moderate 61 of 365 days2025
  • Good
  • Moderate
  • Unhealthy for Sensitive Groups
  • Unhealthy
  • Very Unhealthy
  • Hazardous

Typical and high-end AQI over time

The median is the middle day of the year. The 90th percentile is the level that only the highest 10% of days exceeded.

Median and 90th-percentile daily AQI, by year0501002005: 90th percentile AQI 672006: 90th percentile AQI 612007: 90th percentile AQI 632008: 90th percentile AQI 622009: 90th percentile AQI 612010: 90th percentile AQI 572011: 90th percentile AQI 612012: 90th percentile AQI 582013: 90th percentile AQI 632014: 90th percentile AQI 602015: 90th percentile AQI 572016: 90th percentile AQI 552017: 90th percentile AQI 662018: 90th percentile AQI 572019: 90th percentile AQI 562020: 90th percentile AQI 572021: 90th percentile AQI 602022: 90th percentile AQI 592023: 90th percentile AQI 552024: 90th percentile AQI 632025: 90th percentile AQI 542005: Median AQI 272006: Median AQI 342007: Median AQI 352008: Median AQI 412009: Median AQI 392010: Median AQI 332011: Median AQI 312012: Median AQI 332013: Median AQI 442014: Median AQI 302015: Median AQI 312016: Median AQI 282017: Median AQI 302018: Median AQI 322019: Median AQI 312020: Median AQI 332021: Median AQI 292022: Median AQI 322023: Median AQI 302024: Median AQI 282025: Median AQI 2920052007200920112013201520172019202120232025
  • Median daily AQI
  • 90th-percentile daily AQI

Main pollutant by day, 2025

On each monitored day, the AQI reflects whichever measured pollutant had the highest index. This counts how many days each pollutant set the AQI. A pollutant that was not measured here cannot appear.

PollutantDays as main pollutantShare of monitored days
Fine particles (PM2.5)365100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
2025365304610000295485PM2.5
20243662798412002863155PM2.5
2023363301620000305583PM2.5
20223652837930003259124PM2.5
20213642718814002960155PM2.5
20203662827723203357225PM2.5
2019360293670000315668PM2.5
20183472737211003257172PM2.5
20173652738633003066176PM2.5
2016362303590000285577PM2.5
20153652857082003157159PM2.5
2014365284810000306091PM2.5
20133652231420000446395PM2.5
20123662758920003358137PM2.5
2011352254980000316195PM2.5
2010356267890000335780PM2.5
20093612441170000396188PM2.5
200836623612910004162105PM2.5
20073632551080000356383PM2.5
200635625310120003461107PM2.5
20052742175610002767140PM2.5

What this data can and can’t tell you

It is a county-level summary. EPA reports one AQI per day for the county, based on the monitors operating there. Air at a particular street, school or home can differ, especially near roads, industry or wildfire smoke.

It is not a health assessment. The AQI is EPA’s scale for communicating daily air quality. A county’s history can’t tell you what the health risk is for any particular person. For daily conditions and health guidance, see AirNow.

Rules change over time. EPA has revised AQI breakpoints, most recently for fine particles in 2024, so some year-to-year change can reflect the scale rather than the air.

Counties in Oregon with a similar median AQI in 2025

All monitored counties in Oregon

Source: U.S. EPA AirData, “Annual AQI by County” files for 2005–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem