Clearing the Air: Lower Your Residents’ Exposure to a Cancer-Causing Gas

EPA's Radon Map

You could be exposing your residential community to the United States’ second-leading cause of lung cancer. According to the Environmental Protection Agency, 21,000 people die each year from radon-related lung cancer. This is a risk many multifamily developers are unaware of. Thankfully, there are several inexpensive radon-reduction techniques that you can incorporate into your community to minimize the risk.

Radon is a hazardous gas produced from the breakdown of uranium found in most rocks and soil. When radon decays it can form radioactive dust particles. When inhaled these particles can then alter your DNA and increase the risk of lung cancer. The national average of airborne radon is about 1.3 pCi/L indoors and about 0.4 pCi/L outdoors.

Keeping Radon Off the Radar

Radon should be evaluated during the site and survey phase of your project by your civil engineer. REES believes the initial measurement step should be mandatory for sites in zones 2 and 3.

The Surgeon General, the Centers for Disease Control and the Environmental Protection Agency suggest that while there are no truly safe levels of radon, you should reduce indoor levels of radon to 4.0 pCi/L or lower, which is a reasonably achievable level of radon reduction using currently available cost-effective techniques.

Our residential team is currently working on a 100-unit community in Amarillo, Texas. Amarillo is in Zone 2 according to the EPA, which means the indoor radon levels typically range from 2 to 4 pCi/L. REES worked with the client to provide several options to reduce radon exposure.

REES’ solution for the Amarillo project involved a two-step process. First, we installed a gravel layer instead of select fill under the vapor barrier. This allows the radon gas to be drawn out of the soil below through a network of open-ended PVC piping distributed throughout the foundation area. In this first step, the pipes are gathered into “risers”, approximately 1 pipe per 2,000 square feet, that are capped and labeled a specific distance above the first floor. Some sites dissipate the radon levels quickly during the initial stages of construction. And in those cases, the second phase may never happen.

If the radon levels persist through the initial stages of construction, the second step is to extend the vent pipes through the roof, often aided by booster fans. There are many important details to be aware of that greatly impact the success of this under-slab venting system. The details below are courtesy of the EPA's Building Radon Out. 

REES is equipped with the resources to reduce radon exposure at your community. If you’re developing a project or considering a site to build a new community, contact me to discuss the radon zone of your project and evaluate your options for radon-reduction.