An official website of the United States government
Here's how you know
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
NTA results of the expected 1-min PM2.5 mass concentrations for total PM2.5 (a) and high-varying PM2.5 (b) at the Douglass monitoring location calculated over the six-month study period