Learn the Issues

Presentations on the Black Carbon Diesel Initiative

EPA has presented on the successes of the Black Carbon Diesel Initiative in the Russian Arctic.

2014 National Emission Inventory (NEI) Report

Analysis of the NEI and comparison to previous years of inventory data.

About the Clean Air Technology Center

The Clean Air Technology Center provides resources for emerging and existing air pollution prevention and control technologies and provides public access to data and information on their use, effectiveness and cost.

Tern Island Preliminary Assessment and Technical Support Document

Tern Island Preliminary Assessment and Technical Support Document and summary.

Clean Air Act Permitting Best Practices Documents

Best practices that regulatory agencies, industry and the public may consider when permitting emissions sources under the Clean Air Act (CAA).

Approved Air Quality Implementation Plans in Region 4

Read about the approved State Implementation Plans, Tribal Implementation Plans, as well as any Federal Implementation Plans for Region 4.

Supporting Communities

Landing page for Supporting Communities

Brownfields in EPA Region 8

EPA Region 8 manages Brownfields and Land Revitalization programs in Colorado, Montana, North Dakota, South Dakota, Utah and Wyoming.

Mold Image Library

The image library contains mold-related images in seven categories. There are also animated images that you can choose to view and download. These photos may be used for presentations and educational purposes without contacting EPA.

Mold Remediation in Schools and Commercial Buildings Guide: Chapter 1

The content on this page is based on the guide by the same name. However, updates have been made to some resources and links. Here you can find information on mold prevention and remediation.

A Brief Guide to Mold, Moisture and Your Home

This guide provides information and guidance for homeowners and renters on how to clean up residential mold problems and how to prevent mold growth.

Communicating the Connection Between Climate Change and Heat Health

This page includes presentation and transcript PDFs and mp3s from EPA's August 19, 2015 webcast, "Communicating the Connection Between Climate Change and Heat Health".

Smart Growth and Heat Islands

Information on how smart growth principles can be used to help reduce the heat island effect in cities

Where does radon come from?

Radon-222 is the decay product of radium-226. Radon-222 and its parent, radium-226, are part of the long decay chain for uranium-238. Since uranium is essentially ubiquitous (being or seeming to be everywhere at the same time) in the earth's crust, radium-226 and radon-222 are present in almost all rock and…

Last published: March 27, 2025

What is the average level of radon found in homes in the U.S.?

Based on a national residential radon survey completed in 1991, the average indoor radon level is about 1.3 picocuries per liter (pCi/L) (50 becquerels per cubic meter (Bq/m3)) in air in the United States. The average outdoor level is about 0.4 pCi/L (15 Bq/m3). Learn more about radon by visiting…

Last published: March 27, 2025

Radon Resources

Media Resources, Publications, webinars, Hotlines, NRAM Resources, Media campaigns for TV, radio and print for radon including access to PSAs and other radon media campaigns.

How does radon get into your home?

Any home may have a radon problem. Radon is a radioactive gas. It comes from the natural decay of uranium that is found in nearly all soils. It typically moves up through the ground to the air above and into your home through cracks and other holes in the foundation…

Last published: March 27, 2025