Radon is a chemical element (symbol Rn and atomic number 86).
It is a radioactive, colorless, odorless, tasteless gas, occurring naturally as the decay product of radium.It is one of the heaviest substances that remains a gas under normal conditions and is considered to be a health hazard due to its radioactivity.
Its most stable isotope 222Rn , has a half life of 3.8 days. Due to its high radioactivity, it has been less well-studied by chemists, but a few compounds are known.
Radon is formed as part of the normal radioactive decay chain of uranium. Uranium has been around since the earth was formed and its most common isotope has a very long half-life (4.5 billion years), which is the amount of time required for one-half of uranium to break down. Uranium, radium, and thus radon, will continue to exist indefinitely at about the same levels as they do now.
Radon is responsible for the majority of the mean public exposure to ionizing radiations. It is often the single largest contributor to an individual's background radiation dose, and is the most variable from location to location. Radon gas from natural sources can accumulate in buildings, especially in confined areas such as attics, and basements. It can also be found in some spring waters and hot springs.
Breathing high concentrations of radon can cause lung cancer. Thus, radon is considered a significant contaminant that affects indoor air quality worldwide.
The greatest health risk from radiation in Ireland is caused by radon. It accounts for 56 per cent of the total radiation dose received by the Irish population. Between 150 and 200 lung cancer deaths in Ireland every year can be linked to radon.
HOW DOES RADON GET INTO YOUR HOME?
Any home may have a radon problem. Radon is a radioactive gas. It comes from the natural decay of uranium that is found in nearly all soils. It typically moves up through the ground to the air above and into your home through cracks and other holes in the foundation or radon 'BARRIER'. Your home traps radon inside, where it can build up. Any home may have a radon problem. This means new and old homes, well-sealed and drafty homes, and homes with or without basements.Radon from soil gas is the main cause of radon problems. Sometimes radon enters the home through well water In a small number of homes, the building materials can give off radon, too. However, building materials rarely cause radon problems by themselves.
RADON ENTERS THROUGH
- Cracks in solid floors
- Construction joints
- Cracks in walls
- Gaps in suspended floors
- Gaps around service pipes
- Cavities inside walls
- The water supply
HOW TO TEST YOUR HOME
You can't see radon, but it's not hard to find out if you have a radon problem in your home. Testing can be carried out by an IAQ specialist or with a home test kit.
The amount of radon in the air is measured in Becquerels per cubic metre (Bq/m³)
In reality all homes should be tested - even new homes which have radon barriers installed, as often these barriers are compromised after installation by other construction processes.
It is recommended that where levels are above 200 Bq/m³ remedial action be taken.