CR3 News Magazine 2018 February: Black History Special Edition - Page 42

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What about radon levels?

The WHO Handbook on indoor radon recommends that countries adopt reference levels of the gas of 100 Becquerel per cubic metre (BQ/m3) and not exceeding 300 Bq/m3.

"At the typical action level of 200 Bq/m3, non-smokers have a risk of about 1% (one person in hundred) to get lung cancer. At a 4 times lower level, the risk reduces to 0.3%. In the case of smokers, the corresponding risk values are about 10 times higher," Strydom said.

These risk estimates, he said, wee only true if people were exposed to the levels on average for their entire life.

The NNR added that draft regulations of South Africa had set a reference level of 300 Bq/m3 which could not be exceeded.

"This upper value is yet to be implemented when the regulatory framework for radon in dwellings is finalised for South Africa."

The regulator said this reference level was in line with the International Commission on Radiological Protection (ICRP), the WHO and IAEA recommendations.

Is your kitchen top a health hazard?

There have also been claims that some kitchen counter tops made from granite could also be emitting radon.

The NNR pointed out that only radon on the outermost part of granitic areas had the possibility of escaping the rock.

"There have been studies around the world to test the hypothesis of the kitchen counter top increasing the radon activity concentrations in homes. The conclusion of some studies conducted is that kitchen counter tops do not emit significant amounts of radon that could become of concern from a radiation safety perspective, more so that radon is easily dissipated since South African homes are normally well ventilated."