HonorChemistry 2017: [Nuclear Chemistry] Radon Gas in Homes

Friday, May 5, 2017

[Nuclear Chemistry] Radon Gas in Homes

Radon Gas

Radon is a radioactive gas formed by the radioactive decay of Uranium and is mainly found in rock and soil. Radon is a very common problem in many homes throughout America, affecting the indoor air quality in homes and causing serious health implications.

Chemistry:

Radon is found in the intermediate steps of the decay chain of uranium into lead. Radon is formed by alpha decay (in which the nucleus emits an alpha particle-two protons and two neutrons), and has a half life of 3.8 days. Although radon’s half life doesn’t seem long, nearly 40 trillion tons of uranium exist in the earth’s crust so radon is frequently being regenerated.
Because radon is a noble gas it is chemically inactive (but can react under extreme conditions with highly electronegative elements), and is odorless and colorless. The most common isotopes of radon include radon-222, its most stable isotope, and radon-220.
Radon is a monatomic gas, which allows it to easily penetrate materials such as wood paneling, insulations, paper, and some plastics, and also causes it to easily be inhaled or ingested.

Uranium Decay Series:

Medical effects:

In the 1900’s scientists began to link radon exposure to lung cancer in uranium miners.When radon emits radioactive particles, they can easily be inhaled and attach to the lining of the lungs, ultimately causing severe damage to cells and DNA of the cells. Radon gas is responsible for nearly 20,000 deaths each year and many measures have been taking to limit exposure to these hazardous gases.

Testing for Radon:

Because of its single atom structure, radon can very easily enter a house through tiny cracks, well water, fractured bedrock, and soil. Without proper ventilation, a home can easily become extremely hazardous, increasing the risk of cancer, and affecting the air quality

Radon levels are tested in pCi/L (measure of the rate of the radioactive decay). 1 pCi/L is equal to 2.22 disintegrations per minute.
Recommended action level: 4 pCi/L

Test Devices:

Radon devices are used to measure the radon levels within a home. These devices work by absorbing radon or detecting products from its radioactive decay. The two types of radon test devices include passive and active devices. While passive devices do not require electrical power to function, active devices do.

An example of a passive radon test device is the alpha track detector. This device contains a foil that is marked by alpha particles that strike it. When the testing period expires, it is sent to a laboratory in which scientists enlarge the microscopic markings and calculate the average radon level (using the amount of markings versus the period of time).