EnviroNearby

Giles County, Virginia air quality history

Daily Air Quality Index summaries from EPA monitors in Giles, Virginia, 1990–2025.

94%
Good days in 2025
37
Median daily AQI, 2025
0
Days above 100 in 2025
357
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Giles, Virginia on 357 days. 337 of those days (94%) were in the Good range, and the median daily AQI was 37. That median is about the same as the typical monitored county in Virginia (median 37 across 25 counties), and lower than the typical monitored U.S. county (40). The main pollutant was ozone on 357 days. Across the years with fuller monitoring, the share of Good days rose: an average of 62% in 1990–1992 versus 92% 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%1990: Good 218 of 361 days1990: Moderate 101 of 361 days1990: Unhealthy for Sensitive Groups 39 of 361 days1990: Unhealthy 3 of 361 days19901991: Good 204 of 360 days1991: Moderate 126 of 360 days1991: Unhealthy for Sensitive Groups 26 of 360 days1991: Unhealthy 4 of 360 days1992: Good 252 of 361 days1992: Moderate 97 of 361 days1992: Unhealthy for Sensitive Groups 11 of 361 days1992: Unhealthy 1 of 361 days1993: Good 161 of 307 days1993: Moderate 116 of 307 days1993: Unhealthy for Sensitive Groups 28 of 307 days1993: Unhealthy 2 of 307 days1994: Good 216 of 344 days1994: Moderate 103 of 344 days1994: Unhealthy for Sensitive Groups 21 of 344 days1994: Unhealthy 4 of 344 days1995: Good 133 of 243 days1995: Moderate 76 of 243 days1995: Unhealthy for Sensitive Groups 33 of 243 days1995: Unhealthy 1 of 243 days19951996: Good 128 of 180 days1996: Moderate 44 of 180 days1996: Unhealthy for Sensitive Groups 8 of 180 days1997: Good 236 of 362 days1997: Moderate 86 of 362 days1997: Unhealthy for Sensitive Groups 38 of 362 days1997: Unhealthy 2 of 362 days1998: Good 204 of 348 days1998: Moderate 81 of 348 days1998: Unhealthy for Sensitive Groups 51 of 348 days1998: Unhealthy 12 of 348 days1999: Good 186 of 363 days1999: Moderate 112 of 363 days1999: Unhealthy for Sensitive Groups 54 of 363 days1999: Unhealthy 11 of 363 days2000: Good 205 of 345 days2000: Moderate 99 of 345 days2000: Unhealthy for Sensitive Groups 39 of 345 days2000: Unhealthy 2 of 345 days20002001: Good 244 of 354 days2001: Moderate 92 of 354 days2001: Unhealthy for Sensitive Groups 17 of 354 days2001: Unhealthy 1 of 354 days2002: Good 248 of 362 days2002: Moderate 75 of 362 days2002: Unhealthy for Sensitive Groups 35 of 362 days2002: Unhealthy 4 of 362 days2003: Good 261 of 357 days2003: Moderate 85 of 357 days2003: Unhealthy for Sensitive Groups 10 of 357 days2003: Unhealthy 1 of 357 days2004: Good 296 of 359 days2004: Moderate 55 of 359 days2004: Unhealthy for Sensitive Groups 8 of 359 days2005: Good 261 of 359 days2005: Moderate 85 of 359 days2005: Unhealthy for Sensitive Groups 13 of 359 days20052006: Good 264 of 351 days2006: Moderate 81 of 351 days2006: Unhealthy for Sensitive Groups 6 of 351 days2007: Good 207 of 334 days2007: Moderate 110 of 334 days2007: Unhealthy for Sensitive Groups 17 of 334 days2008: Good 235 of 323 days2008: Moderate 82 of 323 days2008: Unhealthy for Sensitive Groups 6 of 323 days2009: Good 282 of 323 days2009: Moderate 41 of 323 days2010: Good 253 of 348 days2010: Moderate 89 of 348 days2010: Unhealthy for Sensitive Groups 6 of 348 days20102011: Good 264 of 325 days2011: Moderate 60 of 325 days2011: Unhealthy for Sensitive Groups 1 of 325 days2012: Good 280 of 342 days2012: Moderate 60 of 342 days2012: Unhealthy for Sensitive Groups 2 of 342 days2013: Good 332 of 356 days2013: Moderate 24 of 356 days2014: Good 323 of 354 days2014: Moderate 31 of 354 days2015: Good 324 of 357 days2015: Moderate 33 of 357 days20152016: Good 312 of 341 days2016: Moderate 28 of 341 days2016: Unhealthy for Sensitive Groups 1 of 341 days2017: Good 327 of 350 days2017: Moderate 22 of 350 days2017: Unhealthy for Sensitive Groups 1 of 350 days2018: Good 306 of 345 days2018: Moderate 39 of 345 days2019: Good 315 of 344 days2019: Moderate 29 of 344 days2020: Good 337 of 342 days2020: Moderate 5 of 342 days20202021: Good 331 of 358 days2021: Moderate 27 of 358 days2022: Good 329 of 358 days2022: Moderate 29 of 358 days2023: Good 324 of 361 days2023: Moderate 36 of 361 days2023: Unhealthy for Sensitive Groups 1 of 361 days2024: Good 316 of 344 days2024: Moderate 28 of 344 days2025: Good 337 of 357 days2025: Moderate 20 of 357 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 year0501001501990: 90th percentile AQI 1051991: 90th percentile AQI 971992: 90th percentile AQI 801993: 90th percentile AQI 1001994: 90th percentile AQI 971995: 90th percentile AQI 1081996: 90th percentile AQI 771997: 90th percentile AQI 1011998: 90th percentile AQI 1191999: 90th percentile AQI 1222000: 90th percentile AQI 1012001: 90th percentile AQI 902002: 90th percentile AQI 1052003: 90th percentile AQI 742004: 90th percentile AQI 672005: 90th percentile AQI 842006: 90th percentile AQI 712007: 90th percentile AQI 932008: 90th percentile AQI 712009: 90th percentile AQI 542010: 90th percentile AQI 772011: 90th percentile AQI 642012: 90th percentile AQI 582013: 90th percentile AQI 492014: 90th percentile AQI 502015: 90th percentile AQI 502016: 90th percentile AQI 502017: 90th percentile AQI 492018: 90th percentile AQI 512019: 90th percentile AQI 502020: 90th percentile AQI 452021: 90th percentile AQI 492022: 90th percentile AQI 502023: 90th percentile AQI 512024: 90th percentile AQI 502025: 90th percentile AQI 471990: Median AQI 471991: Median AQI 471992: Median AQI 421993: Median AQI 491994: Median AQI 451995: Median AQI 481996: Median AQI 381997: Median AQI 441998: Median AQI 461999: Median AQI 492000: Median AQI 452001: Median AQI 432002: Median AQI 412003: Median AQI 412004: Median AQI 402005: Median AQI 432006: Median AQI 402007: Median AQI 452008: Median AQI 432009: Median AQI 402010: Median AQI 432011: Median AQI 422012: Median AQI 412013: Median AQI 382014: Median AQI 392015: Median AQI 392016: Median AQI 392017: Median AQI 402018: Median AQI 372019: Median AQI 402020: Median AQI 362021: Median AQI 382022: Median AQI 382023: Median AQI 392024: Median AQI 382025: Median AQI 3719901995200020052010201520202025
  • 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
Ozone357100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
2025357337200000374780Ozone
2024344316280000385080Ozone
20233613243610003951101Ozone
20223583292900003850100Ozone
2021358331270000384974Ozone
202034233750000364567Ozone
2019344315290000405084Ozone
2018345306390000375193Ozone
20173503272210004049101Ozone
20163413122810003950115Ozone
2015357324330000395093Ozone
2014354323310000395090Ozone
2013356332240000384984Ozone
20123422806020004158115Ozone
20113252646010004264101Ozone
20103482538960004377119Ozone
20093232824100004054100Ozone
20083232358260004371129Ozone
2007334207110170004593133Ozone
20063512648160004071115Ozone
200535926185130004384150Ozone
20043592965580004067108Ozone
200335726185101004174169Ozone
2002362248753540041105159Ozone
200135424492171004390156Ozone
2000345205993920045101161Ozone
199936318611254110049122172Ozone
19983482048151120046119190Ozone
1997362236863820044101156Ozone
19961801284480003877150Ozone
1995243133763310048108172Ozone
1994344216103214004597166Ozone
19933071611162820049100159Ozone
199236125297111004280156Ozone
1991360204126264004797166Ozone
19903612181013930047105161Ozone

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 Virginia with a similar median AQI in 2025

All monitored counties in Virginia

Source: U.S. EPA AirData, “Annual AQI by County” files for 1990–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem