Radon gas found in Sheffield schools
Work is to be carried out at five primary schools in Sheffield to reduce levels of a radioactive gas.
The city council said the affected schools were Ecclesall Infants, Totley Primary, Birley Primary, Westways Primary and Birley Spa Primary.
The council said radon was naturally occurring and fitting extraction equipment would minimise risks.
The Health Protection Agency said levels in Sheffield were typical of those in schools elsewhere.
Radon emits radiation from the ground and has been linked to lung cancer.
It is a naturally occurring, colourless, odourless, radioactive gas found at varying levels in all houses in the UK and across Europe.
People who are exposed to high levels of radon are more likely to get lung cancer, especially if they are smokers as well.
John Doyle, from Sheffield City Council, said: "The risk of the school environment where there are open classrooms and corridors doesn't really present a significant risk.
"The work we are doing is to be as cautious as possible and to act with national guidelines to make sure there is absolutely no risk whatsoever in Sheffield."
Neil McColl, from the Health Protection Agency (HPA), said: "Parts of South Yorkshire and Derbyshire are, like many other parts of the country, affected by higher than average levels of radon.
"The HPA believes the steps planned by Sheffield City Council to reduce levels will minimise risks from radon in these schools."