Why is exposure to indoor radon gas potentially harmful?
Radon undergoes radioactive breakdown and produces Radon decay products that are also radioactive. Long term exposure to Radon decay products is associated with an increase in the risk of lung cancer. The decay products tend to adhere to dust particles or other surfaces, and if inhaled, can also adhere to the airways of the lung. Alpha particles emitted by two of the Radon decay products (polonium 214 and polonium 218) can strike cells of the lung and damage them. This damage may lead to the formation of cancerous cells. Radon, on the other hand, is almost chemically inert, and an inhaled Radon atom is very likely to be exhaled before it decays. Thus, the main risk from Radon is lung cancer associated with breathing in its short-lived decayed products. This is clearly an adequate basis for concern about indoor Radon exposure. What are the measurement units for radon and radon decay products? For Radon decay products the unit is a working level (WL). A WL is a measure of how much alpha
