Back to Last Page Visited
Navigation Bar Skip Navigation City Council Contact Us Search City Government
Department Contact
Back to our Homepage


Radon is an invisible, odorless gas created by the natural radioactive breakdown of uranium in soil, rock and water. It enters buildings through cracks in floors or walls, construction joints and gaps in suspended floors. It can also enter via service pipes and cavities inside walls. Two houses side-by-side can have different radon levels due to the geology below the homes.

When air containing radon gas is inhaled, ingested or absorbed into the blood stream, sensitive tissue can be exposed to alpha radiation, increasing the risk of cancer. According to the EPA, radon is the leading cause of lung cancer among non-smokers. It is estimated to cause about 21,000 lung cancer deaths per year.

The only way to know if you and your family are at risk from radon is to test your home. The U.S. Surgeon General and EPA recommend that all homes be tested.

Information for use of Safety Siren™ Radon Detectors

The City of Longmont patrons may check out Safety Siren™ radon detectors to test the levels of radon gas in their homes. Contact Library staff to place your name on the waiting list.

Please read and follow all of the instructions for operating the detector-

The City of Longmont does not guarantee the accuracy of the Safety Siren™ radon detectors, and is not responsible for any damages resulting from reliance on the detector results or any decisions that are made based on the detector results. Read the brochure that comes with the detector to ensure proper placement and use.

The Safety Siren™ radon detectors measure short-term (3-30 day) levels of radon in your home, similar to other short-term tests such as charcoal canisters. The detectors measure radon concentrations in picocuries per liter (pCi/L). The detectors can provide a quick "screening" measurement of indoor radon. However, since indoor radon levels can change from room to room and from season to season, a single screening test is not a reliable means of making decisions about radon mitigation.

The EPA recommends that additional testing, including long-term tests, be completed if radon levels are above 4 pCi/L. It is also recommended that additional testing and any evaluation of possible remediation be done by a certified radon professional. "Quick Links" on the right of this page will direct you to the Boulder County website to find information on selection and purchasing long-term tests and to other websites to find mitigation contractors.


Public Works & Natural Resources

Environmental Services

1100 South Sherman Street

Longmont, CO 80501

Phone: (303) 651-8376



EPA Radon Website

EPA Citizens Guide to Radon

National Radon Safety Board

Colorado (CDPHE) Radon Website

CDPHE List of Certified Contractors

Longmont Public Library

Brochure for Detectors

Return to Resource Conservation page.

Return to PWNR home page.

This page was updated August 16, 2013
City of Longmont Public Works & Natural Resources Department

Environmental Services Division