EnviroNearby

Greenville County, South Carolina air quality history

Daily Air Quality Index summaries from EPA monitors in Greenville, South Carolina, 1980–2025.

56%
Good days in 2025
47
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 Greenville, South Carolina on 365 days. 203 of those days (56%) were in the Good range, and the median daily AQI was 47. That median is higher than the typical monitored county in South Carolina (median 43 across 13 counties), and higher than the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 203 days. Across the years with fuller monitoring, the share of Good days fell: an average of 59% in 1980–1982 versus 52% 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%1980: Good 178 of 340 days1980: Moderate 107 of 340 days1980: Unhealthy for Sensitive Groups 38 of 340 days1980: Unhealthy 17 of 340 days19801981: Good 208 of 352 days1981: Moderate 110 of 352 days1981: Unhealthy for Sensitive Groups 25 of 352 days1981: Unhealthy 9 of 352 days1982: Good 230 of 345 days1982: Moderate 89 of 345 days1982: Unhealthy for Sensitive Groups 21 of 345 days1982: Unhealthy 5 of 345 days1983: Good 222 of 365 days1983: Moderate 100 of 365 days1983: Unhealthy for Sensitive Groups 30 of 365 days1983: Unhealthy 13 of 365 days1984: Good 245 of 340 days1984: Moderate 70 of 340 days1984: Unhealthy for Sensitive Groups 22 of 340 days1984: Unhealthy 3 of 340 days1985: Good 219 of 320 days1985: Moderate 76 of 320 days1985: Unhealthy for Sensitive Groups 21 of 320 days1985: Unhealthy 4 of 320 days19851986: Good 238 of 315 days1986: Moderate 48 of 315 days1986: Unhealthy for Sensitive Groups 25 of 315 days1986: Unhealthy 4 of 315 days1987: Good 239 of 358 days1987: Moderate 66 of 358 days1987: Unhealthy for Sensitive Groups 42 of 358 days1987: Unhealthy 11 of 358 days1988: Good 252 of 348 days1988: Moderate 60 of 348 days1988: Unhealthy for Sensitive Groups 25 of 348 days1988: Unhealthy 11 of 348 days1989: Good 227 of 284 days1989: Moderate 50 of 284 days1989: Unhealthy for Sensitive Groups 7 of 284 days1990: Good 219 of 346 days1990: Moderate 79 of 346 days1990: Unhealthy for Sensitive Groups 38 of 346 days1990: Unhealthy 10 of 346 days19901991: Good 111 of 120 days1991: Moderate 8 of 120 days1991: Unhealthy for Sensitive Groups 1 of 120 days1992: Good 233 of 250 days1992: Moderate 17 of 250 days1993: Good 338 of 365 days1993: Moderate 27 of 365 days1994: Good 331 of 363 days1994: Moderate 32 of 363 days1995: Good 293 of 365 days1995: Moderate 72 of 365 days19951996: Good 323 of 366 days1996: Moderate 43 of 366 days1997: Good 329 of 365 days1997: Moderate 36 of 365 days1998: Good 341 of 363 days1998: Moderate 21 of 363 days1998: Unhealthy for Sensitive Groups 1 of 363 days1999: Good 173 of 365 days1999: Moderate 187 of 365 days1999: Unhealthy for Sensitive Groups 5 of 365 days2000: Good 70 of 366 days2000: Moderate 266 of 366 days2000: Unhealthy for Sensitive Groups 29 of 366 days2000: Unhealthy 1 of 366 days20002001: Good 78 of 365 days2001: Moderate 281 of 365 days2001: Unhealthy for Sensitive Groups 5 of 365 days2001: Unhealthy 1 of 365 days2002: Good 80 of 365 days2002: Moderate 281 of 365 days2002: Unhealthy for Sensitive Groups 4 of 365 days2003: Good 80 of 365 days2003: Moderate 279 of 365 days2003: Unhealthy for Sensitive Groups 6 of 365 days2004: Good 85 of 366 days2004: Moderate 277 of 366 days2004: Unhealthy for Sensitive Groups 4 of 366 days2005: Good 63 of 365 days2005: Moderate 290 of 365 days2005: Unhealthy for Sensitive Groups 11 of 365 days2005: Unhealthy 1 of 365 days20052006: Good 60 of 365 days2006: Moderate 298 of 365 days2006: Unhealthy for Sensitive Groups 5 of 365 days2006: Unhealthy 2 of 365 days2007: Good 68 of 365 days2007: Moderate 296 of 365 days2007: Unhealthy for Sensitive Groups 1 of 365 days2008: Good 79 of 366 days2008: Moderate 285 of 366 days2008: Unhealthy for Sensitive Groups 2 of 366 days2009: Good 120 of 365 days2009: Moderate 244 of 365 days2009: Unhealthy for Sensitive Groups 1 of 365 days2010: Good 110 of 365 days2010: Moderate 248 of 365 days2010: Unhealthy for Sensitive Groups 7 of 365 days20102011: Good 126 of 365 days2011: Moderate 234 of 365 days2011: Unhealthy for Sensitive Groups 5 of 365 days2012: Good 170 of 366 days2012: Moderate 195 of 366 days2012: Unhealthy for Sensitive Groups 1 of 366 days2013: Good 216 of 365 days2013: Moderate 149 of 365 days2014: Good 192 of 365 days2014: Moderate 173 of 365 days2015: Good 186 of 365 days2015: Moderate 177 of 365 days2015: Unhealthy for Sensitive Groups 2 of 365 days20152016: Good 191 of 366 days2016: Moderate 169 of 366 days2016: Unhealthy for Sensitive Groups 4 of 366 days2016: Unhealthy 1 of 366 days2016: Very Unhealthy 1 of 366 days2017: Good 195 of 365 days2017: Moderate 170 of 365 days2018: Good 237 of 365 days2018: Moderate 128 of 365 days2019: Good 211 of 365 days2019: Moderate 154 of 365 days2020: Good 234 of 366 days2020: Moderate 131 of 366 days2020: Unhealthy for Sensitive Groups 1 of 366 days20202021: Good 180 of 365 days2021: Moderate 184 of 365 days2021: Unhealthy for Sensitive Groups 1 of 365 days2022: Good 179 of 365 days2022: Moderate 186 of 365 days2023: Good 167 of 365 days2023: Moderate 196 of 365 days2023: Unhealthy for Sensitive Groups 2 of 365 days2024: Good 198 of 363 days2024: Moderate 165 of 363 days2025: Good 203 of 365 days2025: Moderate 162 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 year0501001501980: 90th percentile AQI 1221981: 90th percentile AQI 1001982: 90th percentile AQI 971983: 90th percentile AQI 1121984: 90th percentile AQI 911985: 90th percentile AQI 931986: 90th percentile AQI 971987: 90th percentile AQI 1191988: 90th percentile AQI 1011989: 90th percentile AQI 771990: 90th percentile AQI 1121991: 90th percentile AQI 461992: 90th percentile AQI 491993: 90th percentile AQI 491994: 90th percentile AQI 501995: 90th percentile AQI 551996: 90th percentile AQI 511997: 90th percentile AQI 501998: 90th percentile AQI 471999: 90th percentile AQI 852000: 90th percentile AQI 942001: 90th percentile AQI 822002: 90th percentile AQI 812003: 90th percentile AQI 772004: 90th percentile AQI 802005: 90th percentile AQI 852006: 90th percentile AQI 842007: 90th percentile AQI 822008: 90th percentile AQI 762009: 90th percentile AQI 742010: 90th percentile AQI 782011: 90th percentile AQI 752012: 90th percentile AQI 692013: 90th percentile AQI 622014: 90th percentile AQI 642015: 90th percentile AQI 682016: 90th percentile AQI 662017: 90th percentile AQI 632018: 90th percentile AQI 592019: 90th percentile AQI 632020: 90th percentile AQI 602021: 90th percentile AQI 702022: 90th percentile AQI 662023: 90th percentile AQI 702024: 90th percentile AQI 642025: 90th percentile AQI 641980: Median AQI 481981: Median AQI 451982: Median AQI 411983: Median AQI 441984: Median AQI 401985: Median AQI 411986: Median AQI 371987: Median AQI 391988: Median AQI 351989: Median AQI 351990: Median AQI 411991: Median AQI 291992: Median AQI 331993: Median AQI 331994: Median AQI 311995: Median AQI 381996: Median AQI 351997: Median AQI 331998: Median AQI 301999: Median AQI 522000: Median AQI 632001: Median AQI 612002: Median AQI 592003: Median AQI 592004: Median AQI 612005: Median AQI 622006: Median AQI 642007: Median AQI 612008: Median AQI 592009: Median AQI 552010: Median AQI 562011: Median AQI 562012: Median AQI 522013: Median AQI 462014: Median AQI 492015: Median AQI 492016: Median AQI 502017: Median AQI 492018: Median AQI 442019: Median AQI 462020: Median AQI 442021: Median AQI 512022: Median AQI 512023: Median AQI 522024: Median AQI 482025: Median AQI 471980198519901995200020052010201520202025
  • 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)20356%
Ozone16244%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
20253652031620000476493PM2.5
20243631981650000486499PM2.5
202336516719620005270126PM2.5
20223651791860000516697PM2.5
202136518018410005170101PM2.5
202036623413110004460116PM2.5
20193652111540000466397PM2.5
20183652371280000445977PM2.5
20173651951700000496397PM2.5
201636619116941105066203PM2.5
201536518617720004968112PM2.5
20143651921730000496498PM2.5
20133652161490000466293PM2.5
201236617019510005269112PM2.5
201136512623450005675145PM2.5
201036511024870005678122PM2.5
200936512024410005574101PM2.5
20083667928520005976133PM2.5
20073656829610006182101PM2.5
20063656029852006484162PM2.5
200536563290111006285154PM2.5
20043668527740006180108PM2.5
20033658027960005977118PM2.5
20023658028140005981136PM2.5
20013657828151006182156PM2.5
200036670266291006394197PM2.5
199936517318750005285106PM2.5
19983633412110003047113NO2
1997365329360000335068NO2
1996366323430000355168PM10
1995365293720000385574PM10
1994363331320000315065NO2
1993365338270000334979NO2
1992250233170000334978NO2
1991120111810002946105NO2
19903462197938100041112187Ozone
19892842275070003577115Ozone
19883482526025110035101185Ozone
19873582396642110039119195Ozone
198631523848254003797164Ozone
198532021976214004193177Ozone
198434024570223004091159Ozone
198336522210030130044112185Ozone
198234523089215004197185Ozone
19813522081102590045100177Ozone
198034017810738170048122190Ozone

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 South Carolina with a similar median AQI in 2025

All monitored counties in South Carolina

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