EnviroNearby

Hancock County, West Virginia air quality history

Daily Air Quality Index summaries from EPA monitors in Hancock, West Virginia, 1982–2025.

70%
Good days in 2025
42
Median daily AQI, 2025
1
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 Hancock, West Virginia on 365 days. 255 of those days (70%) were in the Good range, and the median daily AQI was 42. That median is higher than the typical monitored county in West Virginia (median 39 across 12 counties), and about the same as the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 211 days. Across the years with fuller monitoring, the share of Good days fell: an average of 91% in 1982–1984 versus 74% 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%1982: Good 166 of 182 days1982: Moderate 14 of 182 days1982: Unhealthy for Sensitive Groups 2 of 182 days19821983: Good 267 of 299 days1983: Moderate 32 of 299 days1984: Good 274 of 292 days1984: Moderate 18 of 292 days1985: Good 239 of 315 days1985: Moderate 75 of 315 days1985: Unhealthy for Sensitive Groups 1 of 315 days1986: Good 294 of 361 days1986: Moderate 66 of 361 days1986: Unhealthy for Sensitive Groups 1 of 361 days1987: Good 268 of 334 days1987: Moderate 64 of 334 days1987: Unhealthy for Sensitive Groups 2 of 334 days19871988: Good 256 of 363 days1988: Moderate 78 of 363 days1988: Unhealthy for Sensitive Groups 13 of 363 days1988: Unhealthy 14 of 363 days1988: Very Unhealthy 2 of 363 days1989: Good 259 of 362 days1989: Moderate 88 of 362 days1989: Unhealthy for Sensitive Groups 15 of 362 days1990: Good 250 of 358 days1990: Moderate 101 of 358 days1990: Unhealthy for Sensitive Groups 7 of 358 days1991: Good 254 of 365 days1991: Moderate 98 of 365 days1991: Unhealthy for Sensitive Groups 10 of 365 days1991: Unhealthy 3 of 365 days1992: Good 272 of 366 days1992: Moderate 87 of 366 days1992: Unhealthy for Sensitive Groups 7 of 366 days19921993: Good 259 of 365 days1993: Moderate 94 of 365 days1993: Unhealthy for Sensitive Groups 10 of 365 days1993: Unhealthy 2 of 365 days1994: Good 230 of 365 days1994: Moderate 118 of 365 days1994: Unhealthy for Sensitive Groups 16 of 365 days1994: Unhealthy 1 of 365 days1995: Good 236 of 365 days1995: Moderate 97 of 365 days1995: Unhealthy for Sensitive Groups 26 of 365 days1995: Unhealthy 6 of 365 days1996: Good 239 of 366 days1996: Moderate 109 of 366 days1996: Unhealthy for Sensitive Groups 17 of 366 days1996: Unhealthy 1 of 366 days1997: Good 274 of 365 days1997: Moderate 72 of 365 days1997: Unhealthy for Sensitive Groups 17 of 365 days1997: Unhealthy 2 of 365 days19971998: Good 251 of 365 days1998: Moderate 82 of 365 days1998: Unhealthy for Sensitive Groups 22 of 365 days1998: Unhealthy 10 of 365 days1999: Good 200 of 365 days1999: Moderate 135 of 365 days1999: Unhealthy for Sensitive Groups 23 of 365 days1999: Unhealthy 7 of 365 days2000: Good 219 of 366 days2000: Moderate 135 of 366 days2000: Unhealthy for Sensitive Groups 12 of 366 days2001: Good 188 of 365 days2001: Moderate 146 of 365 days2001: Unhealthy for Sensitive Groups 27 of 365 days2001: Unhealthy 4 of 365 days2002: Good 196 of 365 days2002: Moderate 128 of 365 days2002: Unhealthy for Sensitive Groups 24 of 365 days2002: Unhealthy 16 of 365 days2002: Very Unhealthy 1 of 365 days20022003: Good 215 of 365 days2003: Moderate 138 of 365 days2003: Unhealthy for Sensitive Groups 9 of 365 days2003: Unhealthy 3 of 365 days2004: Good 227 of 366 days2004: Moderate 127 of 366 days2004: Unhealthy for Sensitive Groups 11 of 366 days2004: Very Unhealthy 1 of 366 days2005: Good 223 of 365 days2005: Moderate 126 of 365 days2005: Unhealthy for Sensitive Groups 16 of 365 days2006: Good 237 of 365 days2006: Moderate 117 of 365 days2006: Unhealthy for Sensitive Groups 11 of 365 days2007: Good 217 of 365 days2007: Moderate 127 of 365 days2007: Unhealthy for Sensitive Groups 21 of 365 days20072008: Good 239 of 366 days2008: Moderate 116 of 366 days2008: Unhealthy for Sensitive Groups 11 of 366 days2009: Good 267 of 365 days2009: Moderate 97 of 365 days2009: Unhealthy for Sensitive Groups 1 of 365 days2010: Good 233 of 365 days2010: Moderate 122 of 365 days2010: Unhealthy for Sensitive Groups 10 of 365 days2011: Good 259 of 365 days2011: Moderate 100 of 365 days2011: Unhealthy for Sensitive Groups 6 of 365 days2012: Good 252 of 366 days2012: Moderate 102 of 366 days2012: Unhealthy for Sensitive Groups 12 of 366 days20122013: Good 276 of 365 days2013: Moderate 86 of 365 days2013: Unhealthy for Sensitive Groups 3 of 365 days2014: Good 288 of 365 days2014: Moderate 76 of 365 days2014: Unhealthy for Sensitive Groups 1 of 365 days2015: Good 284 of 365 days2015: Moderate 79 of 365 days2015: Unhealthy for Sensitive Groups 2 of 365 days2016: Good 300 of 366 days2016: Moderate 66 of 366 days2017: Good 303 of 365 days2017: Moderate 62 of 365 days20172018: Good 308 of 363 days2018: Moderate 54 of 363 days2018: Unhealthy for Sensitive Groups 1 of 363 days2019: Good 257 of 303 days2019: Moderate 46 of 303 days2020: Good 262 of 307 days2020: Moderate 44 of 307 days2020: Unhealthy for Sensitive Groups 1 of 307 days2021: Good 286 of 364 days2021: Moderate 78 of 364 days2022: Good 317 of 365 days2022: Moderate 48 of 365 days20222023: Good 287 of 364 days2023: Moderate 71 of 364 days2023: Unhealthy for Sensitive Groups 5 of 364 days2023: Unhealthy 1 of 364 days2024: Good 262 of 364 days2024: Moderate 102 of 364 days2025: Good 255 of 365 days2025: Moderate 109 of 365 days2025: Unhealthy for Sensitive Groups 1 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 year0501001501982: 90th percentile AQI 491983: 90th percentile AQI 511984: 90th percentile AQI 471985: 90th percentile AQI 631986: 90th percentile AQI 611987: 90th percentile AQI 611988: 90th percentile AQI 841989: 90th percentile AQI 711990: 90th percentile AQI 701991: 90th percentile AQI 771992: 90th percentile AQI 701993: 90th percentile AQI 751994: 90th percentile AQI 841995: 90th percentile AQI 901996: 90th percentile AQI 841997: 90th percentile AQI 771998: 90th percentile AQI 931999: 90th percentile AQI 932000: 90th percentile AQI 792001: 90th percentile AQI 972002: 90th percentile AQI 1082003: 90th percentile AQI 802004: 90th percentile AQI 772005: 90th percentile AQI 842006: 90th percentile AQI 762007: 90th percentile AQI 872008: 90th percentile AQI 742009: 90th percentile AQI 662010: 90th percentile AQI 772011: 90th percentile AQI 712012: 90th percentile AQI 742013: 90th percentile AQI 622014: 90th percentile AQI 632015: 90th percentile AQI 622016: 90th percentile AQI 542017: 90th percentile AQI 562018: 90th percentile AQI 562019: 90th percentile AQI 542020: 90th percentile AQI 542021: 90th percentile AQI 612022: 90th percentile AQI 532023: 90th percentile AQI 612024: 90th percentile AQI 612025: 90th percentile AQI 641982: Median AQI 311983: Median AQI 281984: Median AQI 311985: Median AQI 361986: Median AQI 341987: Median AQI 351988: Median AQI 391989: Median AQI 401990: Median AQI 391991: Median AQI 401992: Median AQI 361993: Median AQI 411994: Median AQI 431995: Median AQI 431996: Median AQI 421997: Median AQI 401998: Median AQI 411999: Median AQI 462000: Median AQI 442001: Median AQI 492002: Median AQI 482003: Median AQI 452004: Median AQI 402005: Median AQI 412006: Median AQI 422007: Median AQI 442008: Median AQI 422009: Median AQI 372010: Median AQI 432011: Median AQI 392012: Median AQI 412013: Median AQI 372014: Median AQI 362015: Median AQI 362016: Median AQI 362017: Median AQI 382018: Median AQI 352019: Median AQI 402020: Median AQI 372021: Median AQI 382022: Median AQI 342023: Median AQI 362024: Median AQI 412025: Median AQI 421982198719921997200220072012201720222025
  • 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)21158%
Ozone15442%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
202536525510910004264101PM2.5
20243642621020000416197PM2.5
20233642877151003661181Ozone
20223653174800003453100Ozone
2021364286780000386193Ozone
20203072624410003754133Ozone
2019303257460000405493Ozone
20183633085410003556105Ozone
2017365303620000385687Ozone
2016366300660000365493Ozone
20153652847920003662112Ozone
20143652887610003663112Ozone
20133652768630003762140Ozone
2012366252102120004174143Ozone
201136525910060003971133Ozone
2010365233122100004377143Ozone
20093652679710003766105Ozone
2008366239116110004274147Ozone
2007365217127210004487144Ozone
2006365237117110004276150Ozone
2005365223126160004184147Ozone
2004366227127110104077208Ozone
200336521513893004580187Ozone
200236519612824161048108201Ozone
2001365188146274004997159Ozone
2000366219135120004479150PM10
1999365200135237004693192Ozone
1998365251822210004193186Ozone
199736527472172004077185Ozone
1996366239109171004284169PM10
199536523697266004390187PM10
1994365230118161004384154PM10
199336525994102004175192PM10
19923662728770003670136PM10
199136525498103004077185PM10
199035825010170003970147PM10
198936225988150004071150PM10
1988363256781314203984208PM10
19873342686420003561133NO2
19863612946610003461104NO2
19853152397510003663102NO2
1984292274180000314778NO2
1983299267320000285177NO2
19821821661420003149110NO2

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 West Virginia with a similar median AQI in 2025

All monitored counties in West Virginia

Source: U.S. EPA AirData, “Annual AQI by County” files for 1982–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem