Radon
A naturally occurring radioactive gas that enters buildings from the soil and is a recognised cause of lung cancer.
What is Radon?
Radon is produced by the decay of uranium in soil and rock and enters a home through foundation cracks, sump pits, slab penetrations and crawl spaces. It is colourless and odourless, so testing is the only way to identify it. The EPA action level is 4 picocuries per litre, and it recommends considering mitigation between 2 and 4. Levels vary by geography, by house, and seasonally, so a neighbour's result says little about a given property. Radon testing is an ancillary service rather than part of a general inspection, and mitigation typically involves a sub-slab depressurisation system, which is well understood and usually effective.