EnviroNearby

West Baton Rouge Parish, Louisiana air quality history

Daily Air Quality Index summaries from EPA monitors in West Baton Rouge, Louisiana, 1983–2025.

49%
Good days in 2025
51
Median daily AQI, 2025
2
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 West Baton Rouge, Louisiana on 365 days. 180 of those days (49%) were in the Good range, and the median daily AQI was 51. That median is higher than the typical monitored county in Louisiana (median 42 across 21 counties), and higher than the typical monitored U.S. county (40). The main pollutant was fine particles (PM2.5) on 285 days. Across the years with fuller monitoring, the share of Good days fell: an average of 69% in 1983–1985 versus 49% 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%1983: Good 195 of 296 days1983: Moderate 82 of 296 days1983: Unhealthy for Sensitive Groups 14 of 296 days1983: Unhealthy 5 of 296 days19831984: Good 261 of 365 days1984: Moderate 82 of 365 days1984: Unhealthy for Sensitive Groups 17 of 365 days1984: Unhealthy 3 of 365 days1984: Very Unhealthy 2 of 365 days1985: Good 249 of 365 days1985: Moderate 95 of 365 days1985: Unhealthy for Sensitive Groups 12 of 365 days1985: Unhealthy 7 of 365 days1985: Very Unhealthy 2 of 365 days1986: Good 248 of 364 days1986: Moderate 78 of 364 days1986: Unhealthy for Sensitive Groups 30 of 364 days1986: Unhealthy 8 of 364 days1987: Good 224 of 364 days1987: Moderate 101 of 364 days1987: Unhealthy for Sensitive Groups 27 of 364 days1987: Unhealthy 11 of 364 days1987: Very Unhealthy 1 of 364 days1988: Good 273 of 365 days1988: Moderate 58 of 365 days1988: Unhealthy for Sensitive Groups 25 of 365 days1988: Unhealthy 7 of 365 days1988: Very Unhealthy 2 of 365 days19881989: Good 290 of 360 days1989: Moderate 56 of 360 days1989: Unhealthy for Sensitive Groups 9 of 360 days1989: Unhealthy 4 of 360 days1989: Very Unhealthy 1 of 360 days1990: Good 251 of 365 days1990: Moderate 67 of 365 days1990: Unhealthy for Sensitive Groups 29 of 365 days1990: Unhealthy 12 of 365 days1990: Very Unhealthy 6 of 365 days1991: Good 306 of 365 days1991: Moderate 44 of 365 days1991: Unhealthy for Sensitive Groups 11 of 365 days1991: Unhealthy 4 of 365 days1992: Good 293 of 363 days1992: Moderate 55 of 363 days1992: Unhealthy for Sensitive Groups 11 of 363 days1992: Unhealthy 3 of 363 days1992: Very Unhealthy 1 of 363 days1993: Good 312 of 363 days1993: Moderate 43 of 363 days1993: Unhealthy for Sensitive Groups 6 of 363 days1993: Unhealthy 2 of 363 days19931994: Good 304 of 353 days1994: Moderate 39 of 353 days1994: Unhealthy for Sensitive Groups 8 of 353 days1994: Unhealthy 2 of 353 days1995: Good 293 of 363 days1995: Moderate 52 of 363 days1995: Unhealthy for Sensitive Groups 14 of 363 days1995: Unhealthy 4 of 363 days1996: Good 319 of 366 days1996: Moderate 37 of 366 days1996: Unhealthy for Sensitive Groups 5 of 366 days1996: Unhealthy 5 of 366 days1997: Good 311 of 365 days1997: Moderate 42 of 365 days1997: Unhealthy for Sensitive Groups 9 of 365 days1997: Unhealthy 3 of 365 days1998: Good 311 of 365 days1998: Moderate 39 of 365 days1998: Unhealthy for Sensitive Groups 12 of 365 days1998: Unhealthy 2 of 365 days1998: Very Unhealthy 1 of 365 days19981999: Good 78 of 365 days1999: Moderate 267 of 365 days1999: Unhealthy for Sensitive Groups 16 of 365 days1999: Unhealthy 3 of 365 days1999: Very Unhealthy 1 of 365 days2000: Good 96 of 366 days2000: Moderate 221 of 366 days2000: Unhealthy for Sensitive Groups 41 of 366 days2000: Unhealthy 7 of 366 days2000: Very Unhealthy 1 of 366 days2001: Good 103 of 365 days2001: Moderate 251 of 365 days2001: Unhealthy for Sensitive Groups 8 of 365 days2001: Unhealthy 3 of 365 days2002: Good 119 of 362 days2002: Moderate 231 of 362 days2002: Unhealthy for Sensitive Groups 12 of 362 days2003: Good 114 of 365 days2003: Moderate 228 of 365 days2003: Unhealthy for Sensitive Groups 18 of 365 days2003: Unhealthy 3 of 365 days2003: Very Unhealthy 2 of 365 days20032004: Good 103 of 366 days2004: Moderate 244 of 366 days2004: Unhealthy for Sensitive Groups 19 of 366 days2005: Good 69 of 365 days2005: Moderate 280 of 365 days2005: Unhealthy for Sensitive Groups 12 of 365 days2005: Unhealthy 4 of 365 days2006: Good 73 of 365 days2006: Moderate 268 of 365 days2006: Unhealthy for Sensitive Groups 20 of 365 days2006: Unhealthy 4 of 365 days2007: Good 115 of 365 days2007: Moderate 238 of 365 days2007: Unhealthy for Sensitive Groups 11 of 365 days2007: Unhealthy 1 of 365 days2008: Good 116 of 361 days2008: Moderate 240 of 361 days2008: Unhealthy for Sensitive Groups 5 of 361 days20082009: Good 102 of 363 days2009: Moderate 257 of 363 days2009: Unhealthy for Sensitive Groups 4 of 363 days2010: Good 95 of 365 days2010: Moderate 266 of 365 days2010: Unhealthy for Sensitive Groups 4 of 365 days2011: Good 68 of 365 days2011: Moderate 286 of 365 days2011: Unhealthy for Sensitive Groups 10 of 365 days2011: Unhealthy 1 of 365 days2012: Good 132 of 366 days2012: Moderate 232 of 366 days2012: Unhealthy for Sensitive Groups 1 of 366 days2012: Unhealthy 1 of 366 days2013: Good 194 of 365 days2013: Moderate 170 of 365 days2013: Unhealthy for Sensitive Groups 1 of 365 days20132014: Good 169 of 365 days2014: Moderate 195 of 365 days2014: Unhealthy for Sensitive Groups 1 of 365 days2015: Good 215 of 365 days2015: Moderate 147 of 365 days2015: Unhealthy for Sensitive Groups 3 of 365 days2016: Good 213 of 366 days2016: Moderate 151 of 366 days2016: Unhealthy for Sensitive Groups 2 of 366 days2017: Good 199 of 365 days2017: Moderate 163 of 365 days2017: Unhealthy for Sensitive Groups 3 of 365 days2018: Good 218 of 365 days2018: Moderate 144 of 365 days2018: Unhealthy for Sensitive Groups 3 of 365 days20182019: Good 202 of 364 days2019: Moderate 162 of 364 days2020: Good 229 of 366 days2020: Moderate 134 of 366 days2020: Unhealthy for Sensitive Groups 3 of 366 days2021: Good 220 of 365 days2021: Moderate 142 of 365 days2021: Unhealthy for Sensitive Groups 3 of 365 days2022: Good 216 of 364 days2022: Moderate 144 of 364 days2022: Unhealthy for Sensitive Groups 4 of 364 days2023: Good 154 of 362 days2023: Moderate 199 of 362 days2023: Unhealthy for Sensitive Groups 9 of 362 days20232024: Good 198 of 366 days2024: Moderate 166 of 366 days2024: Unhealthy for Sensitive Groups 2 of 366 days2025: Good 180 of 365 days2025: Moderate 183 of 365 days2025: Unhealthy for Sensitive Groups 2 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 year0501001501983: 90th percentile AQI 881984: 90th percentile AQI 721985: 90th percentile AQI 861986: 90th percentile AQI 1011987: 90th percentile AQI 1011988: 90th percentile AQI 971989: 90th percentile AQI 741990: 90th percentile AQI 1121991: 90th percentile AQI 651992: 90th percentile AQI 711993: 90th percentile AQI 561994: 90th percentile AQI 611995: 90th percentile AQI 741996: 90th percentile AQI 561997: 90th percentile AQI 611998: 90th percentile AQI 641999: 90th percentile AQI 872000: 90th percentile AQI 1122001: 90th percentile AQI 832002: 90th percentile AQI 742003: 90th percentile AQI 842004: 90th percentile AQI 832005: 90th percentile AQI 892006: 90th percentile AQI 902007: 90th percentile AQI 782008: 90th percentile AQI 722009: 90th percentile AQI 732010: 90th percentile AQI 792011: 90th percentile AQI 782012: 90th percentile AQI 702013: 90th percentile AQI 622014: 90th percentile AQI 662015: 90th percentile AQI 612016: 90th percentile AQI 612017: 90th percentile AQI 622018: 90th percentile AQI 662019: 90th percentile AQI 622020: 90th percentile AQI 612021: 90th percentile AQI 592022: 90th percentile AQI 632023: 90th percentile AQI 672024: 90th percentile AQI 642025: 90th percentile AQI 611983: Median AQI 431984: Median AQI 411985: Median AQI 431986: Median AQI 441987: Median AQI 461988: Median AQI 401989: Median AQI 361990: Median AQI 401991: Median AQI 341992: Median AQI 371993: Median AQI 321994: Median AQI 341995: Median AQI 351996: Median AQI 341997: Median AQI 331998: Median AQI 361999: Median AQI 592000: Median AQI 572001: Median AQI 562002: Median AQI 542003: Median AQI 562004: Median AQI 562005: Median AQI 592006: Median AQI 602007: Median AQI 562008: Median AQI 552009: Median AQI 552010: Median AQI 592011: Median AQI 592012: Median AQI 542013: Median AQI 492014: Median AQI 522015: Median AQI 462016: Median AQI 472017: Median AQI 482018: Median AQI 462019: Median AQI 472020: Median AQI 442021: Median AQI 462022: Median AQI 462023: Median AQI 522024: Median AQI 492025: Median AQI 511983198819931998200320082013201820232025
  • 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)28578%
Ozone8022%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
202536518018320005161122PM2.5
202436619816620004964101PM2.5
202336215419990005267140PM2.5
202236421614440004663105PM2.5
202136522014230004659150PM2.5
202036622913430004461101PM2.5
201936420216200004762100PM2.5
201836521814430004666129PM2.5
201736519916330004862140PM2.5
201636621315120004761112PM2.5
201536521514730004661143PM2.5
201436516919510005266112PM2.5
201336519417010004962101PM2.5
201236613223211005470159PM2.5
201136568286101005978192PM2.5
20103659526640005979115PM2.5
200936310225740005573126PM2.5
200836111624050005572119PM2.5
2007365115238111005678164PM2.5
200636573268204006090192PM2.5
200536569280124005989179PM2.5
2004366103244190005683150PM2.5
2003365114228183205684207PM2.5
2002362119231120005474143PM2.5
200136510325183005683200PM2.5
2000366962214171057112209PM2.5
199936578267163105987203PM2.5
199836531139122103664205Ozone
19973653114293003361182Ozone
19963663193755003456190NO2
199536329352144003574179Ozone
19943533043982003461172Ozone
19933633124362003256172Ozone
199236329355113103771220Ozone
199136530644114003465190Ozone
19903652516729126040112220Ozone
19893602905694103674210Ozone
198836527358257204097205Ozone
198736422410127111046101227Ozone
1986364248783080044101187Ozone
198536524995127204386205Ozone
198436526182173204172208NO2
198329619582145004388172Ozone

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 Louisiana with a similar median AQI in 2025

All monitored counties in Louisiana

Source: U.S. EPA AirData, “Annual AQI by County” files for 1983–2025 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem