EnviroNearby

Hanover County, Virginia air quality history

Daily Air Quality Index summaries from EPA monitors in Hanover, Virginia, 1980–2025.

97%
Good days in 2025
36
Median daily AQI, 2025
0
Days above 100 in 2025
241
Days with an AQI in 2025 (of 365)

In 2025, EPA reported a daily Air Quality Index (AQI) for Hanover, Virginia on 241 days. 233 of those days (97%) were in the Good range, and the median daily AQI was 36. 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 241 days. Across the years with fuller monitoring, the share of Good days rose: an average of 68% in 1981–1983 versus 94% in 2023–2025.

EPA did not report an AQI for every day of 2025 here (241 of 365 days). Figures describe monitored days only; seasonal monitoring (for example, ozone measured only in warmer months) can make a county look cleaner or dirtier than a full-year record would.

Years with fewer than 120 monitored days (1980) 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%1980: Good 102 of 110 days1980: Moderate 5 of 110 days1980: Unhealthy for Sensitive Groups 2 of 110 days1980: Very Unhealthy 1 of 110 days19801981: Good 238 of 348 days1981: Moderate 72 of 348 days1981: Unhealthy for Sensitive Groups 27 of 348 days1981: Unhealthy 11 of 348 days1982: Good 258 of 362 days1982: Moderate 71 of 362 days1982: Unhealthy for Sensitive Groups 25 of 362 days1982: Unhealthy 7 of 362 days1982: Very Unhealthy 1 of 362 days1983: Good 229 of 360 days1983: Moderate 58 of 360 days1983: Unhealthy for Sensitive Groups 44 of 360 days1983: Unhealthy 26 of 360 days1983: Very Unhealthy 3 of 360 days1984: Good 252 of 349 days1984: Moderate 54 of 349 days1984: Unhealthy for Sensitive Groups 32 of 349 days1984: Unhealthy 11 of 349 days1985: Good 239 of 364 days1985: Moderate 60 of 364 days1985: Unhealthy for Sensitive Groups 51 of 364 days1985: Unhealthy 14 of 364 days19851986: Good 180 of 304 days1986: Moderate 80 of 304 days1986: Unhealthy for Sensitive Groups 36 of 304 days1986: Unhealthy 7 of 304 days1986: Very Unhealthy 1 of 304 days1987: Good 97 of 212 days1987: Moderate 53 of 212 days1987: Unhealthy for Sensitive Groups 36 of 212 days1987: Unhealthy 24 of 212 days1987: Very Unhealthy 2 of 212 days1988: Good 87 of 209 days1988: Moderate 61 of 209 days1988: Unhealthy for Sensitive Groups 32 of 209 days1988: Unhealthy 14 of 209 days1988: Very Unhealthy 15 of 209 days1989: Good 112 of 212 days1989: Moderate 72 of 212 days1989: Unhealthy for Sensitive Groups 21 of 212 days1989: Unhealthy 7 of 212 days1990: Good 121 of 207 days1990: Moderate 60 of 207 days1990: Unhealthy for Sensitive Groups 24 of 207 days1990: Unhealthy 2 of 207 days19901991: Good 95 of 203 days1991: Moderate 58 of 203 days1991: Unhealthy for Sensitive Groups 49 of 203 days1991: Unhealthy 1 of 203 days1992: Good 120 of 210 days1992: Moderate 59 of 210 days1992: Unhealthy for Sensitive Groups 26 of 210 days1992: Unhealthy 5 of 210 days1993: Good 84 of 212 days1993: Moderate 68 of 212 days1993: Unhealthy for Sensitive Groups 45 of 212 days1993: Unhealthy 15 of 212 days1994: Good 108 of 214 days1994: Moderate 65 of 214 days1994: Unhealthy for Sensitive Groups 35 of 214 days1994: Unhealthy 5 of 214 days1994: Very Unhealthy 1 of 214 days1995: Good 121 of 214 days1995: Moderate 57 of 214 days1995: Unhealthy for Sensitive Groups 25 of 214 days1995: Unhealthy 10 of 214 days1995: Very Unhealthy 1 of 214 days19951996: Good 137 of 214 days1996: Moderate 63 of 214 days1996: Unhealthy for Sensitive Groups 14 of 214 days1997: Good 106 of 212 days1997: Moderate 56 of 212 days1997: Unhealthy for Sensitive Groups 35 of 212 days1997: Unhealthy 14 of 212 days1997: Very Unhealthy 1 of 212 days1998: Good 84 of 209 days1998: Moderate 71 of 209 days1998: Unhealthy for Sensitive Groups 34 of 209 days1998: Unhealthy 18 of 209 days1998: Very Unhealthy 2 of 209 days1999: Good 107 of 213 days1999: Moderate 52 of 213 days1999: Unhealthy for Sensitive Groups 36 of 213 days1999: Unhealthy 17 of 213 days1999: Very Unhealthy 1 of 213 days2001: Good 127 of 214 days2001: Moderate 60 of 214 days2001: Unhealthy for Sensitive Groups 21 of 214 days2001: Unhealthy 6 of 214 days20012002: Good 101 of 213 days2002: Moderate 67 of 213 days2002: Unhealthy for Sensitive Groups 29 of 213 days2002: Unhealthy 12 of 213 days2002: Very Unhealthy 4 of 213 days2003: Good 127 of 202 days2003: Moderate 53 of 202 days2003: Unhealthy for Sensitive Groups 18 of 202 days2003: Unhealthy 4 of 202 days2004: Good 151 of 212 days2004: Moderate 46 of 212 days2004: Unhealthy for Sensitive Groups 15 of 212 days2005: Good 125 of 213 days2005: Moderate 63 of 213 days2005: Unhealthy for Sensitive Groups 23 of 213 days2005: Unhealthy 2 of 213 days2006: Good 133 of 211 days2006: Moderate 64 of 211 days2006: Unhealthy for Sensitive Groups 12 of 211 days2006: Unhealthy 2 of 211 days20062007: Good 113 of 211 days2007: Moderate 76 of 211 days2007: Unhealthy for Sensitive Groups 21 of 211 days2007: Unhealthy 1 of 211 days2008: Good 146 of 213 days2008: Moderate 50 of 213 days2008: Unhealthy for Sensitive Groups 16 of 213 days2008: Unhealthy 1 of 213 days2009: Good 176 of 214 days2009: Moderate 37 of 214 days2009: Unhealthy for Sensitive Groups 1 of 214 days2010: Good 115 of 213 days2010: Moderate 84 of 213 days2010: Unhealthy for Sensitive Groups 13 of 213 days2010: Unhealthy 1 of 213 days2011: Good 149 of 206 days2011: Moderate 47 of 206 days2011: Unhealthy for Sensitive Groups 10 of 206 days20112012: Good 160 of 208 days2012: Moderate 43 of 208 days2012: Unhealthy for Sensitive Groups 3 of 208 days2012: Unhealthy 2 of 208 days2013: Good 172 of 196 days2013: Moderate 23 of 196 days2013: Unhealthy for Sensitive Groups 1 of 196 days2014: Good 175 of 200 days2014: Moderate 25 of 200 days2015: Good 189 of 214 days2015: Moderate 25 of 214 days2016: Good 174 of 207 days2016: Moderate 31 of 207 days2016: Unhealthy for Sensitive Groups 2 of 207 days20162017: Good 215 of 238 days2017: Moderate 23 of 238 days2018: Good 209 of 238 days2018: Moderate 29 of 238 days2019: Good 216 of 243 days2019: Moderate 27 of 243 days2020: Good 243 of 245 days2020: Moderate 2 of 245 days2021: Good 228 of 245 days2021: Moderate 17 of 245 days20212022: Good 226 of 239 days2022: Moderate 13 of 239 days2023: Good 213 of 229 days2023: Moderate 15 of 229 days2023: Unhealthy for Sensitive Groups 1 of 229 days2024: Good 228 of 245 days2024: Moderate 17 of 245 days2025: Good 233 of 241 days2025: Moderate 8 of 241 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 year0501001502001980: 90th percentile AQI 481981: 90th percentile AQI 1081982: 90th percentile AQI 1001983: 90th percentile AQI 1401984: 90th percentile AQI 1081985: 90th percentile AQI 1221986: 90th percentile AQI 1081987: 90th percentile AQI 1541988: 90th percentile AQI 1771989: 90th percentile AQI 1121990: 90th percentile AQI 1051991: 90th percentile AQI 1291992: 90th percentile AQI 1191993: 90th percentile AQI 1431994: 90th percentile AQI 1191995: 90th percentile AQI 1221996: 90th percentile AQI 931997: 90th percentile AQI 1361998: 90th percentile AQI 1501999: 90th percentile AQI 1402001: 90th percentile AQI 1052002: 90th percentile AQI 1432003: 90th percentile AQI 1012004: 90th percentile AQI 902005: 90th percentile AQI 1052006: 90th percentile AQI 932007: 90th percentile AQI 1012008: 90th percentile AQI 932009: 90th percentile AQI 672010: 90th percentile AQI 972011: 90th percentile AQI 842012: 90th percentile AQI 742013: 90th percentile AQI 542014: 90th percentile AQI 542015: 90th percentile AQI 542016: 90th percentile AQI 582017: 90th percentile AQI 502018: 90th percentile AQI 542019: 90th percentile AQI 542020: 90th percentile AQI 452021: 90th percentile AQI 492022: 90th percentile AQI 492023: 90th percentile AQI 502024: 90th percentile AQI 492025: 90th percentile AQI 461980: Median AQI 201981: Median AQI 391982: Median AQI 401983: Median AQI 401984: Median AQI 391985: Median AQI 411986: Median AQI 431987: Median AQI 611988: Median AQI 671989: Median AQI 491990: Median AQI 461991: Median AQI 541992: Median AQI 471993: Median AQI 671994: Median AQI 501995: Median AQI 491996: Median AQI 451997: Median AQI 511998: Median AQI 641999: Median AQI 502001: Median AQI 462002: Median AQI 542003: Median AQI 442004: Median AQI 442005: Median AQI 472006: Median AQI 472007: Median AQI 492008: Median AQI 442009: Median AQI 402010: Median AQI 492011: Median AQI 442012: Median AQI 432013: Median AQI 392014: Median AQI 422015: Median AQI 402016: Median AQI 392017: Median AQI 392018: Median AQI 402019: Median AQI 412020: Median AQI 342021: Median AQI 382022: Median AQI 392023: Median AQI 402024: Median AQI 392025: Median AQI 361980198519901995200120062011201620212025
  • 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
Ozone241100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
202524123380000364677Ozone
2024245228170000394974Ozone
20232292131510004050101Ozone
2022239226130000394977Ozone
2021245228170000384987Ozone
202024524320000344564Ozone
2019243216270000415490Ozone
2018238209290000405497Ozone
2017238215230000395087Ozone
20162071743120003958105Ozone
2015214189250000405474Ozone
2014200175250000425493Ozone
20131961722310003954140Ozone
20122081604332004374169Ozone
201120614947100004484133Ozone
201021311584131004997154Ozone
20092141763710004067115Ozone
200821314650161004493159Ozone
2007211113762110049101179Ozone
200621113364122004793174Ozone
2005213125632320047105169Ozone
200421215146150004490129Ozone
2003202127531840044101185Ozone
20022131016729124054143207Ozone
2001214127602160046105192Ozone
19992131075236171050140204Ozone
1998209847134182064150209Ozone
19972121065635141051136219Ozone
199621413763140004593143Ozone
19952141215725101049122203Ozone
1994214108653551050119213Ozone
1993212846845150067143200Ozone
1992210120592650047119190Ozone
199120395584910054129166Ozone
1990207121602420046105159Ozone
1989212112722170049112174Ozone
19882098761321415067177226Ozone
1987212975336242061154208Ozone
1986304180803671043108201Ozone
19853642396051140041122200Ozone
19843492525432110039108197Ozone
19833602295844263040140213Ozone
1982362258712571040100201Ozone
19813482387227110039108182Ozone
1980110102520102048208Ozone

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 1980–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem