Shasta, California Air Quality

Shasta County, California (CA)

→ Stableover 10 years

Air Quality Grade

57/100

Current Median AQI

Good

5-Year Avg AQI

10-Year Change

Worse

Unhealthy Days/yr

5-year average

Ozone

Primary Pollutant

Ground-Level Ozone

10-Year AQI Trend

The solid line shows the median AQI each year. The dashed line shows the 90th percentile (worst 10% of days).

Air Quality Day Breakdown

Number of days per year in each EPA AQI category. Green = Good (AQI 0-50), Yellow = Moderate (51-100), Orange = Unhealthy for Sensitive Groups (101-150), Red = Unhealthy or worse (151+).

Year-by-Year Data

Year	Median AQI	90th Pct	Max AQI	Good Days	Moderate	Unhealthy+	Pollutant
2023	45	64	1435	247	112	6	Ozone
2022	45	71	119	253	106	6	Ozone
2021	46	93	240	222	111	32	Ozone
2020	41	67	171	286	72	8	Ozone
2019	42	54	100	306	58	0	Ozone
2018	43	84	206	272	72	21	Ozone
2017	44	84	159	260	91	14	Ozone
2016	41	74	140	296	56	14	Ozone
2015	44	84	157	252	100	13	Ozone
2014	43	71	126	272	87	6	Ozone

What This Means for Shasta County Residents

Shasta, California has received an Air Quality Grade of C (57/100) based on a decade of EPA monitoring data. The current median AQI of 45 falls in the "Good" range.

The primary pollutant affecting this area is Ground-Level Ozone. Over the past 5 years, this area has averaged 10 unhealthy air quality days per year — days when sensitive groups (children, elderly, those with respiratory conditions) should limit outdoor activity.