Data / Rankings / Share of days unhealthy for sensitive groups or worse (US EPA AQI) / Counties in New Jersey

Counties in New Jersey by share of days unhealthy for sensitive groups or worse (US EPA AQI)

Hunterdon County had the highest share of days unhealthy for sensitive groups or worse (US EPA AQI) of 20 counties in 1980, at 32.1%. Salem County had the lowest, at 0%. The median was 14.1%. Source: EPA.

Keep it in a collection in your library.
Highest32.1Hunterdon County
Lowest0Salem County
Median14.120 counties

Map of counties, 1980

Atlantic County: 20.1 %Bergen County: 14.2 %Burlington County: 23.4 %Camden County: 23.5 %Cape May County: 23.7 %Cumberland County: 13 %Essex County: 15.1 %Gloucester County: 0 %Hudson County: 13.4 %Hunterdon County: 32.1 %Mercer County: 20.1 %Middlesex County: 14 %Monmouth County: 12.8 %Morris County: 19 %Ocean County: 0.3 %Passaic County: 0.6 %Salem County: 0 %Somerset County: 6.8 %Union County: 19.4 %Warren County: 0.6 %
  • Under 0.6
  • 0.6 to 13
  • 13 to 17
  • 17 to 21
  • 21 and over
  • No data
%, 1980. Hatched areas have no value for this period. Source: Invokely calculation with data from EPA. Boundaries: U.S. Census Bureau cartographic boundary files.

All counties, 1980

Hunterdon County: 32.1 %Hunterdon County32.1Cape May County: 23.7 %Cape May County23.7Camden County: 23.5 %Camden County23.5Burlington County: 23.4 %Burlington County23.4Atlantic County: 20.1 %Atlantic County20.1Mercer County: 20.1 %Mercer County20.1Union County: 19.4 %Union County19.4Morris County: 19 %Morris County19Essex County: 15.1 %Essex County15.1Bergen County: 14.2 %Bergen County14.2Middlesex County: 14 %Middlesex County14Hudson County: 13.4 %Hudson County13.4Cumberland County: 13 %Cumberland County13Monmouth County: 12.8 %Monmouth County12.8Somerset County: 6.8 %Somerset County6.8Passaic County: 0.6 %Passaic County0.6Warren County: 0.6 %Warren County0.6Ocean County: 0.3 %Ocean County0.3Gloucester County: 0 %Gloucester County0Salem County: 0 %Salem County0Hunterdon County: 32.1 %Hunterdon County32.1Cape May County: 23.7 %Cape May County23.7Camden County: 23.5 %Camden County23.5Burlington County: 23.4 %Burlington County23.4Atlantic County: 20.1 %Atlantic County20.1Mercer County: 20.1 %Mercer County20.1Union County: 19.4 %Union County19.4Morris County: 19 %Morris County19Essex County: 15.1 %Essex County15.1Bergen County: 14.2 %Bergen County14.2Middlesex County: 14 %Middlesex County14Hudson County: 13.4 %Hudson County13.4Cumberland County: 13 %Cumberland County13Monmouth County: 12.8 %Monmouth County12.8Somerset County: 6.8 %Somerset County6.8Passaic County: 0.6 %Passaic County0.6Warren County: 0.6 %Warren County0.6Ocean County: 0.3 %Ocean County0.3Gloucester County: 0 %Gloucester County0Salem County: 0 %Salem County0
%. Source: Invokely calculation with data from EPA. Retrieved 2026-10-12.

Full ranking

RankCounties1980 (%)
1Hunterdon County32.1
2Cape May County23.7
3Camden County23.5
4Burlington County23.4
5Atlantic County20.1
5Mercer County20.1
7Union County19.4
8Morris County19
9Essex County15.1
10Bergen County14.2
11Middlesex County14
12Hudson County13.4
13Cumberland County13
14Monmouth County12.8
15Somerset County6.8
16Passaic County0.6
16Warren County0.6
18Ocean County0.3
19Gloucester County0
19Salem County0

Other periods

About this ranking

Days with a daily Air Quality Index above 100 (unhealthy for sensitive groups, unhealthy, very unhealthy or hazardous) as a percentage of the days of the year with an AQI in a US county. Calculated by Invokely from the day counts in the EPA AirData annual summaries; the counts are stored with each value.

Use the share rather than the number of days to compare counties, since the days with an AQI differ. United States counties with air quality monitors only, about 1,000 of some 3,100 in recent years; a county without monitors has no value. The number of days with an AQI differs between counties because some monitors run only in the ozone season.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. Equal values share a rank.

How to cite

U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.

Citation styles

The publisher is the author. Invokely is named only as the place the figures were read, where a style asks for it.

APA 7

U.S. Environmental Protection Agency. (2026). EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts (Counties in New Jersey by share of days unhealthy for sensitive groups or worse (US EPA AQI), 1980) [Data set]. Retrieved October 12, 2026, from https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual

MLA 9

EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts, Counties in New Jersey by share of days unhealthy for sensitive groups or worse (US EPA AQI), 1980. U.S. Environmental Protection Agency, 13 July 2026, https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Invokely, https://invokely.ai/rankings/unhealthy-air-quality-days-share/new-jersey-counties?period=1980. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Environmental Protection Agency. 2026. EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts. Counties in New Jersey by share of days unhealthy for sensitive groups or worse (US EPA AQI), 1980. Dataset. Accessed October 12, 2026. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Also distributed by Invokely, https://invokely.ai/rankings/unhealthy-air-quality-days-share/new-jersey-counties?period=1980.

Harvard

U.S. Environmental Protection Agency (2026) EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts, Counties in New Jersey by share of days unhealthy for sensitive groups or worse (US EPA AQI), 1980 [Dataset]. Available at: https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual, via Invokely: https://invokely.ai/rankings/unhealthy-air-quality-days-share/new-jersey-counties?period=1980 (Accessed: 12 October 2026).

BibTeX
@misc{environmental_counties_in_new_jersey_1980,
  author = {{U.S. Environmental Protection Agency}},
  title = {{EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts: Counties in New Jersey by share of days unhealthy for sensitive groups or worse (US EPA AQI), 1980}},
  year = {2026},
  howpublished = {Data set},
  url = {https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual},
  urldate = {2026-10-12},
  note = {Accessed via Invokely, https://invokely.ai/rankings/unhealthy-air-quality-days-share/new-jersey-counties?period=1980. Publisher attribution: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts. https://aqs.epa.gov/aqsweb/airdata/download\_files.html\#Annual. Retrieved 2026-10-12.},
}
RIS
TY  - DATA
AU  - U.S. Environmental Protection Agency
TI  - EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts: Counties in New Jersey by share of days unhealthy for sensitive groups or worse (US EPA AQI), 1980
PY  - 2026
DA  - 2026/07/13
PB  - U.S. Environmental Protection Agency
DB  - Invokely
UR  - https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual
L2  - https://invokely.ai/rankings/unhealthy-air-quality-days-share/new-jersey-counties?period=1980
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/unhealthy-air-quality-days-share/new-jersey-counties?period=1980.
N1  - Publisher attribution: U.S. Environmental Protection Agency, Air Quality System, AirData. EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts. https://aqs.epa.gov/aqsweb/airdata/download_files.html#Annual. Retrieved 2026-10-12.
ER  -
Embed this chart

Paste this code into a web page or a blog post. The chart shows the latest figures as they are published, with the source and a link back to this page.

Sites that read oEmbed links, such as WordPress, can show the chart when you paste the link to this page.

Use this data in your AI agent

Invokely serves this figure to AI assistants through MCP and to code through a REST API, with the source and citation attached. Ask your assistant:

Rank Counties in New Jersey by share of days unhealthy for sensitive groups or worse (US EPA AQI) using official data, and cite the source.
rank_places {"indicator":"aqi_unhealthy_sensitive_or_worse_days_share","level":"province","within":"New Jersey","limit":10}
GET https://invokely.ai/api/v1/rank?indicator=aqi_unhealthy_sensitive_or_worse_days_share&level=province&within=New%20Jersey&limit=10

Connect Claude, ChatGPT or Cursor in one step. The trial answers 25 calls a day without an account.

Questions

Which county has the highest share of days unhealthy for sensitive groups or worse (US EPA AQI)?

Hunterdon County, with 32.1% in 1980, according to EPA.

Which county has the lowest share of days unhealthy for sensitive groups or worse (US EPA AQI)?

Salem County, with 0% in 1980.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Environmental Protection Agency, EPA AirData annual AQI by county: days with an AQI above 100 as a share of days with an AQI, calculated with stored counts. Retrieved 2026-10-12.

Share of days unhealthy for sensitive groups or worse (US EPA AQI): other rankings

Counties in New Jersey: more rankings