Radon is a naturally occurring radioactive gas that has an atomic number of 86 and an atomic mass of 222u. It is found naturally and cannot be produced commercially. Despite the fact that it has a very short half-life of 3.8 days it has a relatively heavy concentration and composition in the atmosphere. It is found in the atmosphere, soil and water reservoirs under the surface of the earth. The amount of radon that is naturally present in the environment is very minute and is not dangerous at all. Radon becomes dangerous when there is an abrupt increase in its concentration due to natural causes and one is exposed to this high amount for the prolonged amount of time.
There are three major sources of radon namely:
- Radioactive Decay
- Decomposition of Radon
- Underground Water Reservoirs
Most of the radioactive elements exist underneath the surface of the earth deep inside the core of the planet. These elements not only exist there, also decay producing radiations and radioactive components termed as daughter elements. These elements are highly permeable and can pass through any surface no matter how thick it is. Therefore when they undergo radioactive decay in the core of the earth, they pass through the thickness of the earth and reach the surface. Here radon is dissolved in the air and exists there as a permanent component of the atmosphere. It does not stop decaying at any point and continues to reproduce its daughter elements. Hence there is a constant increase in its concentration every minute. When this radon comes to the surface of the earth and is dissolved in the air there, this way serves as the most significant entrance for Radon in home.
Decomposition of Radon:
The decomposition of radon itself contributes to its stability and constant composition in the environment. Radon starts to decompose as soon as it is produced. The disintegration of radon is a chain reaction i.e. the products themselves promote and spread the reaction. During the disintegration reaction two products are formed. The first product is a radioactive element itself known as daughter element of radon and the second product of the radioactive decay is a radiation. This chain disintegration reaction itself is one of the most common sources of radon in homes because when the radon poisoned air is entrapped in houses this factor contributes to its multiplication.
Underground Water Reservoirs
As mentioned earlier the radioactive elements exist underground, therefore, the residues of the radioactive decomposition are also found underneath. Another important fact is that most a huge proportion of water that is utilized for drinking purposes is drawn from water sources that are under the surface of the earth. When the radon existing there undergoes decomposition bits and residues of radon tend to dissolve in this water and utilize this water as a medium to make their way to the surface of the earth. The supply of underground is therefore termed as the most common source of radon in homes.