Bad Air Days in Edgefield County, South Carolina: under 1 a Year

under 1 bad air day a year

Rare: among the cleanest-air counties EPA monitors. Ranked 778 of 996 monitored counties, where 1 is worst.

What makes them bad: mostly particles: smoke and dust (83% particle days).

The bad-air season here

Most bad days here fall in November and May and June. 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 9 bad days a year; in 2016 to 2025, under 1. The air has improved. The worst recent year was 2016, with 5 bad days on 347 monitored days.

Date	AQI	Main pollutant
2016-11-11	171	PM2.5
2016-11-15	166	PM2.5
2020-06-27	115	PM2.5
2016-11-14	114	PM2.5
2016-11-16	110	PM2.5

An ordinary day in Edgefield

Across 3,561 monitored days from 2016 to 2025, the air in Edgefield County rated Good on 69% of them, close to the 72% typical of monitored counties, and Moderate on 31%. The median day sat at AQI 42; one day in ten went above 59.

The pollutant setting the AQI on an ordinary day here:

fine particles (PM2.5)64%2,279 days
ozone36%1,282 days

Every recent year on file

Year	Days monitored	Good	Moderate	Over 100	Over 150	Median AQI	Highest AQI
2025*	365	248	117	0	0	43	98
2024	365	231	134	0	0	44	98
2023	365	217	148	0	0	44	96
2022	364	250	114	0	0	43	74
2021	354	261	93	0	0	39	87
2020	366	307	58	1	0	37	115
2019	361	234	127	0	0	43	90
2018	330	250	80	0	0	39	90
2017	344	234	110	0	0	44	84
2016	347	224	118	5	2	45	171
2015	291	241	49	1	0	37	105
2014	276	192	84	0	0	41	71
2013	325	232	93	0	0	39	78
2012	332	182	150	0	0	49	82
2011	338	177	160	1	0	49	107
2010	353	257	96	0	0	41	97

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

Nearby counties on file

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.