Radon - a gas second only to cigarette smoke in its ability to cause lung cancer - can't be seen, smelled or tasted.
But now might be the perfect time to detect it.
Colorado public health officials are urging residents this month to test for the noxious gas, which exists at high levels across Colorado and, in particular, the Pikes Peak region. The reason: Winter allows for the most convenient time to test because most tests must be done when doors and windows are closed, according to the Colorado Department of Public Health and Environment.
Radon is a naturally occurring, radioactive byproduct of decomposing uranium - a metal found in the ground across Colorado, often in trace amounts.
The gas does not immediately sicken people, but prolonged exposure - generally over the span of years and decades - can be harmful. Each year, more than 20,000 people die of lung cancer caused by the gas, according to the Centers for Disease Control and Prevention.
Existing without an odor, taste or color, the gas is pulled from the ground and into houses, usually via holes in crawlspaces or though spaces between walls. To a lesser extent, it can seep through walls, much like water seeping through the floor of a basement.
Unusually large concentrations of uranium in Pikes Peak granite - while not nearly enough to be mined - have caused high radon levels here.
On average, half of the houses in El Paso County are at least 50 percent above the Environmental Protection Agency's recommended maximum exposure level, said Jim Burkhart, who founded the University of Colorado at Colorado Springs' radon lab and heads the university's physics department.
While the EPA recommends levels not meet or exceed 4 picoCuries per liter, houses in El Paso County average 6 pCi/L - with some as high as 100 pCi/L, he said. Test readings typically rise the farther from the center of Colorado Springs you travel, but radon levels can prove fickle.
"The radon can vary as much as a factor of 10 from one house to the next adjacent house," Burkhart said.
Home or business mitigation typically involves installing a fan to help move the gas safely from the affected building.
The key is first getting tested. El Paso County Public Health is offering free tests, and the UCCS Radon Lab sells more sophisticated tests for $25.
"You can't even go to the movies and get popcorn for $25," Burkhart said. "And yet this test can save your life."
Contact Jakob Rodgers: 476-1654