EnviroNearby

Halifax County, North Carolina air quality history

Daily Air Quality Index summaries from EPA monitors in Halifax, North Carolina, 1992–1997.

97%
Good days in 1997
19
Median daily AQI, 1997
0
Days above 100 in 1997
59
Days with an AQI in 1997 (of 365)

In 1997, EPA reported a daily Air Quality Index (AQI) for Halifax, North Carolina on 59 days. 57 of those days (97%) were in the Good range, and the median daily AQI was 19. That median is lower than the typical monitored county in North Carolina (median 47 across 35 counties), and lower than the typical monitored U.S. county (39). The main pollutant was coarse particles (PM10) on 59 days.

EPA did not report an AQI for every day of 1997 here (59 of 365 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 1997; EPA's files for 1998–2025 contain no row for it, which usually means its monitors stopped reporting.

Years with fewer than 120 monitored days (1992, 1993, 1994, 1995, 1996, 1997) 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%1992: Good 13 of 13 days19921993: Good 50 of 50 days19931994: Good 56 of 56 days19941995: Good 52 of 52 days19951996: Good 46 of 47 days1996: Moderate 1 of 47 days19961997: Good 57 of 59 days1997: Moderate 2 of 59 days1997
  • 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 year0501001992: 90th percentile AQI 321993: 90th percentile AQI 381994: 90th percentile AQI 301995: 90th percentile AQI 321996: 90th percentile AQI 331997: 90th percentile AQI 341992: Median AQI 201993: Median AQI 211994: Median AQI 191995: Median AQI 191996: Median AQI 211997: Median AQI 19199219931994199519961997
  • Median daily AQI
  • 90th-percentile daily AQI

Main pollutant by day, 1997

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)59100%

Year-by-year data

Annual AQI summary by year
YearDays with AQIGoodModerateUnhealthy for Sensitive GroupsUnhealthyVery UnhealthyHazardousMedian AQI90th pct.Max AQIMain pollutant
1997595720000193454PM10
1996474610000213351PM10
1995525200000193248PM10
1994565600000193044PM10
1993505000000213850PM10
1992131300000203235PM10

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.

All monitored counties in North Carolina

Source: U.S. EPA AirData, “Annual AQI by County” files for 1992–1997 (EPA download page). EPA file dates: 2026-06-26. Imported into EnviroNearby November 5, 2026. How we use this data · Report a problem