EnviroNearby

Churchill County, Nevada air quality history

Daily Air Quality Index summaries from EPA monitors in Churchill, Nevada, 1993–2025.

85%
Good days in 2025
40
Median daily AQI, 2025
0
Days above 100 in 2025
344
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Churchill, Nevada on 344 days. 293 of those days (85%) were in the Good range, and the median daily AQI was 40. That median is about the same as the typical monitored county in Nevada (median 42 across 9 counties), and about the same as the typical monitored U.S. county (40). The main pollutant was ozone on 344 days. Across the years with fuller monitoring, the share of Good days held roughly steady: an average of 82% in 2005–2007 versus 82% in 2023–2025.

Years with fewer than 120 monitored days (1993, 1994, 1995, 1996, 1997, 1998) are shown in the table but left out of comparisons and trend statements.

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%1993: Good 29 of 35 days1993: Moderate 6 of 35 days19931994: Good 43 of 45 days1994: Moderate 2 of 45 days1995: Good 45 of 47 days1995: Moderate 2 of 47 days19951996: Good 52 of 54 days1996: Moderate 2 of 54 days1997: Good 53 of 53 days19971998: Good 24 of 25 days1998: Moderate 1 of 25 days2005: Good 207 of 213 days2005: Moderate 6 of 213 days20052006: Good 170 of 214 days2006: Moderate 43 of 214 days2006: Unhealthy for Sensitive Groups 1 of 214 days2007: Good 134 of 197 days2007: Moderate 61 of 197 days2007: Unhealthy for Sensitive Groups 2 of 197 days20072008: Good 179 of 201 days2008: Moderate 19 of 201 days2008: Unhealthy for Sensitive Groups 3 of 201 days2009: Good 170 of 195 days2009: Moderate 24 of 195 days2009: Unhealthy for Sensitive Groups 1 of 195 days20092010: Good 186 of 207 days2010: Moderate 21 of 207 days2011: Good 208 of 210 days2011: Moderate 2 of 210 days20112012: Good 205 of 206 days2012: Moderate 1 of 206 days2013: Good 153 of 210 days2013: Moderate 57 of 210 days20132014: Good 153 of 211 days2014: Moderate 58 of 211 days2015: Good 209 of 261 days2015: Moderate 50 of 261 days2015: Unhealthy for Sensitive Groups 2 of 261 days20152016: Good 284 of 351 days2016: Moderate 66 of 351 days2016: Unhealthy for Sensitive Groups 1 of 351 days2017: Good 283 of 350 days2017: Moderate 64 of 350 days2017: Unhealthy for Sensitive Groups 3 of 350 days20172018: Good 256 of 332 days2018: Moderate 71 of 332 days2018: Unhealthy for Sensitive Groups 5 of 332 days2019: Good 323 of 353 days2019: Moderate 30 of 353 days20192020: Good 336 of 363 days2020: Moderate 25 of 363 days2020: Unhealthy for Sensitive Groups 2 of 363 days2021: Good 271 of 362 days2021: Moderate 81 of 362 days2021: Unhealthy for Sensitive Groups 9 of 362 days2021: Unhealthy 1 of 362 days20212022: Good 330 of 349 days2022: Moderate 19 of 349 days2023: Good 295 of 354 days2023: Moderate 59 of 354 days20232024: Good 280 of 358 days2024: Moderate 77 of 358 days2024: Unhealthy for Sensitive Groups 1 of 358 days2025: Good 293 of 344 days2025: Moderate 51 of 344 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 year0501001993: 90th percentile AQI 641994: 90th percentile AQI 381995: 90th percentile AQI 421996: 90th percentile AQI 371997: 90th percentile AQI 341998: 90th percentile AQI 352005: 90th percentile AQI 482006: 90th percentile AQI 642007: 90th percentile AQI 712008: 90th percentile AQI 512009: 90th percentile AQI 512010: 90th percentile AQI 512011: 90th percentile AQI 452012: 90th percentile AQI 412013: 90th percentile AQI 612014: 90th percentile AQI 642015: 90th percentile AQI 612016: 90th percentile AQI 612017: 90th percentile AQI 612018: 90th percentile AQI 672019: 90th percentile AQI 502020: 90th percentile AQI 502021: 90th percentile AQI 742022: 90th percentile AQI 472023: 90th percentile AQI 582024: 90th percentile AQI 612025: 90th percentile AQI 541993: Median AQI 321994: Median AQI 251995: Median AQI 251996: Median AQI 211997: Median AQI 231998: Median AQI 112005: Median AQI 412006: Median AQI 442007: Median AQI 462008: Median AQI 402009: Median AQI 432010: Median AQI 402011: Median AQI 332012: Median AQI 322013: Median AQI 462014: Median AQI 462015: Median AQI 442016: Median AQI 412017: Median AQI 432018: Median AQI 442019: Median AQI 412020: Median AQI 402021: Median AQI 442022: Median AQI 392023: Median AQI 432024: Median AQI 442025: Median AQI 4019931995199720052007200920112013201520172019202120232025
  • 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
Ozone344100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
2025344293510000405477Ozone
20243582807710004461105Ozone
2023354295590000435890Ozone
20223493301900003947100Ozone
20213622718191004474159Ozone
20203633362520004050147Ozone
2019353323300000415080Ozone
20183322567150004467129Ozone
20173502836430004361129Ozone
20163512846610004161108Ozone
20152612095020004461133Ozone
20142111535800004664100Ozone
2013210153570000466187Ozone
201220620510000324151Ozone
201121020820000334577Ozone
2010207186210000405180Ozone
20091951702410004351101Ozone
20082011791930004051126Ozone
20071971346120004671105Ozone
20062141704310004464112Ozone
200521320760000414874Ozone
1998252410000113563PM10
1997535300000233449PM10
1996545220000213774PM10
1995474520000254260PM10
1994454320000253856PM10
1993352960000326479PM10

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 Nevada with a similar median AQI in 2025

All monitored counties in Nevada

Source: U.S. EPA AirData, “Annual AQI by County” files for 1993–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem