Radon is a colourless, odourless radioactive gas. It is formed by the radioactive decay of the small amounts of uranium that occur naturally in all rocks and soils. Radioactive elements decay and emit radiation. Any exposure to this type of radiation is a risk to health - radiation is a form of energy and can cause damage in living tissues increasing the risk of cancer in both humans and animals.
For most people, the greatest exposure to radon occurs in the home. The concentration of radon in a home depends on:
Certain areas in the UK are more prone to Radon exposure than others particularly in the East Midlands and the South West but there are pockets just about everywhere in the country. It is common in and around granite and other igneous rocks and soil where the gas is transferred through the pores in the rock. It is interesting to note that not all granitic regions are prone to high emissions of radon, Aberdeen, for instance, commonly known as Granite City, is situated in a very low radon area.
The primary routes of potential human exposure to radon are inhalation and ingestion. Radon in the ground, groundwater, or building materials enters working and living spaces and disintegrates into its decay products. Although high concentrations of radon in groundwater may contribute to radon exposure through ingestion, the inhalation of radon released from water is usually more important.
High levels of radiation are dangerous, as radon causes radioactive dust in the air. This can become trapped in our airways, and continue to emit radiation, including dangerous alpha particles. The damage this causes to tissues increases the risk of lung cancer, with this risk going up as levels of radon and exposure times rise. Due to the nature of Radon it can be described as an invisible killer, like carbon monoxide.
Radon is the number one cause of lung cancer among non-smokers, according to EPA estimates. Overall, long term exposure to radon is the second leading cause of lung cancer. Radon is responsible for about 21,000 lung cancer deaths every year. About 2,900 of these deaths occur among people who have never smoked. The early signs and symptoms of lung cancer to be aware of;
Those at most risk of exposure to Radon and therefore it’s dangers are people that are subject to confined air spaces, particularly in underground work areas such as mines and buildings. However, Radon can also affect water supplies, as elevated radon levels can occur in private water supplies.
However, it’s not only humans that can contract health conditions as a result of exposure to radon gas. Laboratory animal research programs on the effects of radon-daughter inhalation are being carried out in laboratories in both the United States and France. While much of the early work explored acute effects, more recent experiments involving chronic exposure have resulted in the induction of lung cancer in both rats and dogs. Unfortunately, animals are just as susceptible as developing cancerous cells as humans so exposure to radon gas is just as dangerous.
Animal studies have been conducted for over 50 years to examine the respiratory effects of pollutants in the air of mines. This work, emphasizing respiratory cancer, has provided important data on exposure-response relationships and the interactions among the harmful agents to which miners are exposed. Many of the initial studies were concerned with early effects or short-term pathological changes. In many of the studies, exposures were based primarily on radon-gas concentrations, with little or no consideration of radon-daughter concentrations, which have been shown to contribute the greatest radiation dose to the lung. Two American research centers—the University of Rochester and the Pacific Northwest Laboratory (PNL)—and the Compagnie Generale des Matieres Nucleaires (COGEMA) laboratory in France have contributed most of the experimental data on radon-daughter inhalation by laboratory animals.
Radon is measured in units called becquerels, and these are calculated per cubic metre. Generally speaking, a level below 100 Bq/m³ is considered low risk, and the UK average is far below this at 20 Bq/m³. As the radon level rises past the 100 Bq/m³ point, the risk begins to increase. Testing radon levels is simple, there are two different ways to test your home for radon; short term testing and long term testing. Short term testing involves placing a radon testing device in your home for at least 7 days to ensure an accurate reading is gathered. Long term testing involves placing two detectors in your home, one in the living area and one in an occupied bedroom after 90 days you then send the data off. You can even purchase the tests in some hardware stores.
If you live in an area where high radon levels are more likely, it is recommended that you test your home. You can see the level of Radon in your area by using the Public Health England's interactive map. You can also order a Radon detector, like a carbon monoxide detector they can be placed on a shelf but they can be damaged by heat or submersion in water and should not be opened. If you opt to do this and discover levels to be within the safe zone, you can rest assured that there is a low risk. If, however, you find that there are dangerous levels of radon in your home, there are actions you can take to lower them to within the safe limits.
The Environmental Protection Agency (USA) and the Public Health England (UK) both offer advise on radon including a UK national radon action plan. The report describes: the properties and health risks of radon; its distribution within the UK and routes of exposure; how radon exposure is assessed and managed in homes, workplaces, new buildings, water supplies and building materials; the approaches to communicating on radon with groups of people affected. The report identifies new topics for consideration.
There are different radon mitigation systems for example a radon sump, an active radon sump, fitted with a fan, is an effective way to reduce indoor radon levels. Sumps work best under solid floors and under suspended floors if the ground is covered with concrete or a membrane. Occasionally, passive sumps without a fan may reduce radon levels. Another highly effective way of reducing high levels of radon in your property is Positive Input Ventilation.
Positive input ventilation brings fresh air into a home, and dilutes the radon. The flow of air and radon from the ground may also be reduced. A positive ventilation system can be effective in homes with radon levels up to and around 500 Bq m-3. Positive Input Ventilation (PIV) work as a whole house ventilation system and create fresh and healthy living environments by supplying fresh, filtered air into a property at a continuous rate throughout. The units are either situated in the loft in a house, or on a wall in an apartment to deliver whole house ventilation. They operate quietly in the background, eliminating condensation and preventing mould whilst maintaining healthy indoor air. All of our PIV units are fitted with an ultra-low watt motor to ensure minimum energy consumption.
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