Other “very unhealthy” locations have the following Index readings:
- 244: Suburban Washington/Maryland.
- 252: Southern coastal New Jersey.
- 252: Kent County, Del.
- 270: Philadelphia.
- 291: Greater New Castle County, Del.
- 293: Northern Virginia.
- 293: Metropolitan Washington.
These two locations are in the “hazardous” or health emergency warning category:
- 309: Lehigh Valley, Pa.
- 399: Susquehanna Valley, Pa.
To check an air quality advisory in your area, enter your ZIP code at AirNow.gov.
A version of this article first appeared on WebMD.com.