Radon, the invisible, odorless gas that is the product of decaying uranium, poses more of a threat to New Mexicans than they might realize, according to the state's chief radon expert.

The gas, which rises from the soil and rocks and gets trapped inside buildings, is the second leading cause of lung cancer after cigarette smoking, and the primary cause of lung cancer in non-smokers, said Michael Taylor, citing data from the National Cancer Institute.

It's estimated that radon causes 21,000 cancer deaths every year.

The gas is particularly insidious because it strikes silently where we live, work and play — inside our homes and offices.

Taylor, the indoor-radon outreach coordinator for the state Environment Department, notes we can't really get away from the gas, but at lower levels it is not particularly harmful.

As to whether you should have your home tested for radon, it's a matter of, "How lucky do you feel?" said Taylor, who recommends all New Mexico residences be tested.

Taylor will address the dangers of radon, how to test for it and what to do about it if the levels present a problem at a free workshop June 16 at Santa Fe Community College.

The Homeowners Guide to Radon class will be held from 4 to 6 p.m. in the Jemez Rooms 1 and 2 on the college campus, 6401 Richards Ave.

New Mexico is among the states with the highest incidences of dangerous radon levels because of the large amounts of uranium in the soil and its numerous mountain ranges, Taylor said.

"There is no place in New Mexico that it isn't found," he said. The most prominent region is a roughly triangular area north from Bernalillo through the foothills and mountainous regions of Santa Fe to the Colorado border, east through Rio Arriba County and west to Union County.

That's according to map of radon zones published by the Environmental Protection Agency.

However, dangerous "hot spots" can be found throughout the state, and there is no accurate way to determine exactly where they are without the home and building testing, Taylor said.

Besides being found in uranium decay, radon is a common element of granite and volcanic ash and cinders.

Despite its presence, reducing radon's threat is relatively simple.

"It's easy to measure and it's easy to take care of (with proper ventilation)," said Virginia McLemore, senior economic geologist with the New Mexico Bureau of Geology, a division of New Mexico University of Mining and Technology.

She cited a previous problem with high levels of radon in Carlsbad Caverns National Park, which was remedied with installation of high-powered fans.

Radon can enter homes through cracks in floors, walls or foundations. It also can be released from building materials, water or wells that contain radon, according to the state Environment Department. Radon levels often are higher in homes that are well insulated, tightly sealed, and/or built on uranium-rich soil. Because of their closeness to the ground, basement and first floors typically have the highest radon levels.

Radon test kits, generally consisting of activated charcoal, are commonly available at home-improvement and other department stores. They also can be obtained at the state Health Department on a first-come, first-served basis, and through the state's radon consultant, Alpha Energy Laboratories in Carrollton, Texas.

Steps to reduce radon in a home include sealing floors and walls, increasing under-floor ventilation, installing a radon sump system, or installing a whole-house positive pressurization and ventilation system that in essence attracts the radon into a pipe system that releases the radon out of the home.

Those wishing to attend the June 16 SFCC radon class should call 505-428-1414 or email jeannemarie.crockett@sfcc.edu. Walk-ins are welcome.