EnviroNearby

Comal County, Texas air quality history

Daily Air Quality Index summaries from EPA monitors in Comal, Texas, 1991–1992.

100%
Good days in 1992
13
Median daily AQI, 1992
0
Days above 100 in 1992
14
Days with an AQI in 1992 (of 366)

In 1992, EPA reported a daily Air Quality Index (AQI) for Comal, Texas on 14 days. 14 of those days (100%) were in the Good range, and the median daily AQI was 13. That median is lower than the typical monitored county in Texas (median 38.5 across 20 counties), and lower than the typical monitored U.S. county (37). The main pollutant was coarse particles (PM10) on 14 days.

EPA did not report an AQI for every day of 1992 here (14 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.

Years with fewer than 120 monitored days (1991, 1992) 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%1991: Good 51 of 52 days1991: Moderate 1 of 52 days19911992: Good 14 of 14 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 year0501001991: 90th percentile AQI 331992: 90th percentile AQI 191991: Median AQI 211992: Median AQI 1319911992
  • 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
Coarse particles (PM10)14100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
1992141400000131920PM10
1991525110000213366PM10

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 Texas with a similar median AQI in 1992

All monitored counties in Texas

Source: U.S. EPA AirData, “Annual AQI by County” files for 1991–1992 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem