Radon is causing natural radioactivity

Natural radioactive substances are everywhere. One of these is uranium found in the bedrock and soil. When uranium gets degraded several new radioactive materials are forming (uranium chain). The final product is stable lead. We find radon in this chain.

 

Radon is radioactive noble gas

Radon is a gas that has little ability to bind to solids. Radon atoms can therefore easily escape and get into the air we breathe.

 

Why is radon a problem? 

Radon can be problem in kindergartens, schools, homes and workplaces.

The reason lies in soil conditions with alum shales and uranium containing granite. Combined with sand and soils, in Norwegian building customs, this has brought us to the top of the world in radon problems.

Norwegian plan and building regulations

PBL §8 - 33, section 1 general requirements:  
Ground building structures shall be performed in the way that contaminations from the ground can not penetrate into the construction works and health. 


PBL §8 - 33, section 4 radon: 
Building design should ensure that people who are living in a building can not be exposed to radon concentration indoors because it may increase the risk to human health. 

Guideline to technical regulations of plan and building as specified in §8 - 33: 
Contaminants supplied from indoor air in the building ground are preliminary humidity and radon.
Structures that are in contact with the ground must be performed very tight so that contamination from the ground can not penetrate into the construction works and cause health risks.

Norwegian Radiation Protection Authority – NRPA  ("Statens Strålevern")
http://www.nrpa.no/en/
 
About radon in Wikipedia: 
https://en.wikipedia.org/wiki/Radon

Estimates of risk for radon exposure are based on epidemiological studies, among both miners and the residential environment.  The studies show clear connections between exposure to radon and the occurrence of lung cancer. 

Ratings of health risks associated with radon exposure are performed by number of international organizations such as the World Health Organization (WHO) and the International Radiation Protection Commission (ICRP). The estimates of risk provided by the Norwegian Radiation Protection Authority – NRPA (Statens strålevern) are based on these assignments. With the concentrations we have in Norway, radon in indoor air can be a major cause to roughly 5-15% of all lung cancer cases in the population. 

It might be large local variations in the same area. It is almost impossible to predict radon concentration in a building without making a measurement. Even in the same building field it can be large variations from one property to another.

• Radon and it’s substances emits alpha rays.
• Alpha rays can damage living cells. This way they develop into cancer cells.
• Alpha rays stopes easily in the air and don’t need to penetrate through the skin surface.
• The only important part of the body that gets radiation doses in respirator system are bronchi and lungs.
• Many individual circumstances are essential, but the risk for lung cancer will in all cases increase the concentration of radon and how long you stay in premises.
   

It occurs in total approximately 1900 new cases of lung cancers in Norway each year. It is estimated that approximately 300 of these cases could have radon exposure at home. What kind of risk represents radon depends on how high concentration of it is in the air there one is staying.

Source: Norwegian Radiation Protection Authority – NRPA ("Statens strålevern")

Lung cancer
http://www1.umn.edu
https://www.regjeringen.no/en/id4/

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