Bad Air Days in Kanawha County, West Virginia: under 1 a Year

under 1 bad air day a year

Rare: among the cleanest-air counties EPA monitors. Ranked 818 of 996 monitored counties, where 1 is worst.

What makes them bad: mostly ozone: summer smog (20% particle days).

The bad-air season here

Most bad days here fall in June and April. Averaged over 2016 to 2025.

What actually helps here

Bad air days are rare here. A standard furnace filter is enough; no purifier needed for outdoor air.
On the odd bad day, check AirNow and keep windows shut.

The worst days on file

In 2000 to 2009 this county averaged 20 bad days a year; in 2016 to 2025, under 1. The air has improved. The worst recent year was 2016, with 2 bad days on 354 monitored days.

Date	AQI	Main pollutant
2023-06-29	153	PM2.5
2016-04-19	119	Ozone
2016-04-20	108	Ozone
2017-06-03	105	Ozone
2018-06-16	105	Ozone

The air on a normal day

Across 3,622 monitored days from 2016 to 2025, the air in Kanawha County rated Good on 70% of them, close to the 72% typical of monitored counties, and Moderate on 30%. The median day sat at AQI 43; one day in ten went above 58.

The pollutant setting the AQI on an ordinary day here:

fine particles (PM2.5)59%2,152 days
ozone38%1,384 days
carbon monoxide2%86 days

Every recent year on file

Year	Days monitored	Good	Moderate	Over 100	Over 150	Median AQI	Highest AQI
2025*	365	281	84	0	0	39	69
2024	364	283	81	0	0	40	90
2023	361	254	106	1	1	42	153
2022	353	253	100	0	0	41	90
2021	365	239	126	0	0	44	97
2020	366	287	79	0	0	41	85
2019	365	262	103	0	0	44	93
2018	364	217	146	1	0	46	105
2017	365	214	150	1	0	47	105
2016	354	245	107	2	0	41	119
2015	359	281	76	2	1	36	167
2014	364	273	91	0	0	38	100
2013	349	258	89	2	0	39	112
2012	337	200	124	13	0	46	140
2011	361	231	119	11	3	41	164
2010	365	219	143	3	1	44	154

*2025 may be a partial year in EPA's file.

Nearby counties on file

Ohio County1/yr
Berkeley County1/yr
Hancock Countyunder 1/yr
Wood Countyunder 1/yr
Marshall Countyunder 1/yr
Cabell Countyunder 1/yr
Brooke Countyunder 1/yr
Marion Countythin data

How this is counted

A bad air day is a day the county's daily AQI from EPA AirData went above 100, the level where EPA tells children, older adults and people with asthma or heart disease to cut back outdoors. Monitors do not run every day, so yearly counts are scaled to 365 days. This is the record, not today's air: for that, check AirNow. More on the method in how the county numbers are made, on the AQI 100 line in what counts as a bad air day, and on why a purifier does not touch ozone in smoke vs ozone.