CR3 News Magazine 2018 February: Black History Special Edition - Page 41

It noted that some studies indicated that there was a slight increase in radon background in areas where there were mining activities, where uranium or associated radionuclides occured in the ore or the waste products.

Strydom pointed out though that while regions with uranium deposits or base-rock containing uranium were generally prone to higher radon concentrations, this factor could be overshadowed by the soil type or the natural ventilation of the house.

"Mining and groundwork activities may result in elevated concentrations if the house is very near to the activities (< 100m) although this has not been shown unequivocally. The effect is highly dependent on weather conditions and season."

The NNR claimed that there were mitigating circumstances that decreased radon levels significantly in our homes and workplaces. These, it said, were good ventilation habits and fair weather throughout most of the year.

"It has been proven that ventilation of an area with high radon can significantly decrease the radon and therefore the risk," it said.

"In countries which experience extensive winters and cold bouts of weather, houses are well built and insulated from the outside, so if any radon come into the house, through ground, the soil or crawl space, not much can be flushed out from normal ventilation processes. But in South Africa, the air is circulated through normal ventilation processes unlike double glazed windows and sealed houses which leads to radon accumulation."

The World Health Organisation (WHO) recommends reducing radon exposure in

your house by:

- increasing under-floor ventilation;

- installing a radon sump system in the basement or under a solid floor;

- avoiding the passage of radon from the basement into living rooms;

- sealing floors and walls and;

- improving the ventilation of the house.

continued on next page ...

The only government body to regulate radiation levels in the country is the NNR, however, their concern and the regulations are aimed at protection against radiation that occurs as a result of human intervention such as mining.

The NNR told Health24 in an emailed response to questions that in several countries abroad it is a legislative requirement to have the radon measured and if need be, mitigated to levels that is considered safe.

"In many of these [countries], the by-laws of certain municipalities also require that new houses that are built, must conform to certain radon levels and be certified safe in a certain range. This also includes houses that are being sold 'second hand' which must conform to a certain value."

It said it was not yet a legislative requirement in South Africa for houses to be tested for radon; however, it added that plans are afoot to change this. "The country is on initial stages of setting up a regulatory framework for radon in dwellings."

Where are the radon hot spots in SA?

The NNR further admitted to Health24 that the identification of the geographical or geological areas which are classified as radon prone areas had not been done for the country.

"Increased levels of radon are expected to increase in certain geological formations, but the actual situation for the country is still to be established."

*1 becquerel is equal to 1 radioactive disintegration per second. picocuries per litre (pCi/L) (United States) 1 pCi/L is equal to 37 Bq/m3. 200 Bq/m3 is equal to 5.4 pCi/L.