Radon Gas vs Radon Decay Products

The RDPs are different from radon in several ways, including:

• They are short-lived (all less than 30 minutes).            
• They are left with static electric charges as a result of the radioactive decay.
• They are chemically reactive.
• They are solid particles, rather than gases, that act like invisible aerosols in the air.

These properties allow them to easily attach themselves to solid objects such as dust, smoke, walls, floors, clothing, or any other object. If the RDPs attach to surfaces, such as walls or floors, they are said to be “plated out”, that is, no longer floating about in the air. If they attach to dust or smoke particles they can be carried into the lungs, where they can lead to lung cancer (See Figure 2-9).

The radioactive decay chain for radon begins with uranium.  Uranium decays through several intermediate steps to produce radium, which in turn produces radon.  Radon then decays into other substances (Radon Decay Products or RDPs) that are also radioactive.  The process continues until non-radioactive lead is created.