Radon: an odorless, colorless and insidious contaminant

Although often relegated to the shadows of public notoriety, radon remains an elusive adversary, lurking discreetly in enclosed environments. As a radioactive gas with no warning signs, radon is unfortunately forging a reputation as a “silent killer”, emerging as the leading cause of lung cancer in non-smokers.

In this blog post, we examine the presence of radon in the air of indoor environments, assess the risks it poses to the health of building occupants, and look at the crucial measures aimed at detecting and mitigating this invisible threat, which can seep into any structure in contact with the ground.

Presence in the environment

Variable concentrations of uranium can be detected in the soil. This radioactive mineral, which is widespread throughout the planet, undergoes natural decay, giving rise to various radioactive by-products, including radon, which is present in gaseous form. After its genesis, radon rises to the surface and is released into the outside air. Outdoors, its rapid dilution generally reduces concentrations to levels that are not harmful to the population.

Presence in buildings

When radon emerges from the ground inside a building, instead of dispersing into the outside air, it can accumulate in concentrations that are potentially hazardous to occupants’ health. The main entry points for radon, generally located on the lower level (in contact with the ground), frequently result in higher concentrations on this floor. It’s important to remember that a new, impeccable foundation is not immune to radon infiltration. If the radon concentration in indoor air exceeds 200 Becquerels/m³, Health Canada recommends the implementation of corrective measures to reduce the health risks to occupants.

Risk variability

Despite the possibility of an increased density of radon-affected buildings in certain areas, it remains difficult to determine defined risk zones. The uneven distribution of affected structures is evident in all regions of Quebec. In short, it is reasonable to estimate that a building with an enclosed or poorly ventilated space in contact with the ground has a one-in-ten chance of having an excessively high radon concentration in the air.

Prevention and remediation

Being colorless and odorless, with no short-term symptoms, the presence of radon in indoor air must be detected using specific measuring equipment (dosimeters). Although this is a simple and cost-effective method of analysis, dosimeters must be installed with care to guarantee reliable results. Faced with the insidious threat of radon and its long-term effects on health, caution is essential. Early detection of this invisible gas remains the cornerstone of prevention of the risks associated with the presence of this “silent killer” in our buildings.

Mitigating radon in the air is both controllable and cost-effective, guaranteeing a healthy environment and preserving the health of occupants and workers alike. In short, radon control is an essential investment in the long-term well-being of building occupants.

How can we support you?

Our Building Sciences team can help you with sampling strategies, setting up sampling campaigns and interpreting the results.