EnviroNearby

Livingston County, Illinois air quality history

Daily Air Quality Index summaries from EPA monitors in Livingston, Illinois, 1988–1992.

81%
Good days in 1992
38
Median daily AQI, 1992
10
Days above 100 in 1992
217
Days with an AQI in 1992 (of 366)

In 1992, EPA reported a daily Air Quality Index (AQI) for Livingston, Illinois on 217 days. 176 of those days (81%) were in the Good range, and the median daily AQI was 38. That median is higher than the typical monitored county in Illinois (median 33 across 21 counties), and about the same as the typical monitored U.S. county (37). The main pollutant was ozone on 217 days.

EPA did not report an AQI for every day of 1992 here (217 of 366 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.

The most recent year with data for this county is 1992; EPA's files for 1993–2025 contain no row for it, which usually means its monitors stopped reporting.

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%1988: Good 108 of 200 days1988: Moderate 46 of 200 days1988: Unhealthy for Sensitive Groups 37 of 200 days1988: Unhealthy 9 of 200 days19881989: Good 148 of 212 days1989: Moderate 49 of 212 days1989: Unhealthy for Sensitive Groups 14 of 212 days1989: Unhealthy 1 of 212 days19891990: Good 228 of 277 days1990: Moderate 45 of 277 days1990: Unhealthy for Sensitive Groups 4 of 277 days19901991: Good 262 of 346 days1991: Moderate 59 of 346 days1991: Unhealthy for Sensitive Groups 18 of 346 days1991: Unhealthy 6 of 346 days1991: Very Unhealthy 1 of 346 days19911992: Good 176 of 217 days1992: Moderate 31 of 217 days1992: Unhealthy for Sensitive Groups 9 of 217 days1992: Unhealthy 1 of 217 days1992
  • 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 year0501001501988: 90th percentile AQI 1361989: 90th percentile AQI 901990: 90th percentile AQI 711991: 90th percentile AQI 871992: 90th percentile AQI 801988: Median AQI 491989: Median AQI 441990: Median AQI 371991: Median AQI 381992: Median AQI 3819881989199019911992
  • Median daily AQI
  • 90th-percentile daily AQI

Main pollutant by day, 1992

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
Ozone217100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
19922171763191003880156Ozone
199134626259186103887203Ozone
19902772284540003771122Ozone
198921214849141004490161Ozone
1988200108463790049136179Ozone

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 Illinois with a similar median AQI in 1992

All monitored counties in Illinois

Source: U.S. EPA AirData, “Annual AQI by County” files for 1988–1992 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem