• Radon was officially discovered in 1900 by Friedrich Ernst Dorn, who named it "Radium Emanation."
• In 1910, radon was formally identified as a new element in the periodic table of elements, a radioactive noble gas, Rn 222.
• Radon comes from the natural decay of uranium and radium present in the earth's crust.
• As it decays, radon causes the formation of "Radon Decay Products" (RDPs), including Polonium 218 and Lead 214, which are solid elements.
• Radon is a heavy gas that tends to accumulate in basements.

In the open air, radon is present in small quantities, about 10 bq/m3, so it does not pose a danger. However, in our homes, it can accumulate in significant quantities in the basement and pose a significant health hazard to occupants.