Wi-Fi networks came under attack last night from a BBC investigation that claimed that radio frequency (RF) radiation levels from Wi-Fi networks in schools are up to three times those of a mobile phone mast.
The investigation also found, though, that the signals could be hundreds of times stronger and still stay within Government health guidelines.
The BBC's Panorama programme has investigated the potential health hazards of Wi-Fi networks in schools. It measured the RF radiation in one school and found that the radiation from the school's network was as much as 600 times below the Government's safety limits for RF radiation.
A Panorama spokesperson confirmed to OUT-LAW that its reference to the highest levels being three times those of a mobile phone mast compared Wi-Fi radiation levels in a classroom with mobile phone mast radiation levels near the school, not the levels at the mast.
BT has rejected accusations that Wi-Fi is dangerous. "As our work with local councils in the creation of Wireless Cities continues, we are very conscious of our responsibility to the public, employees and customers," said the telco in a statement.
"BT is absolutely committed to ensuring the technology we install is safe. Speculation about health issues in relation to mobile phones, mobile base stations and related wireless products is still very much in the public eye and we take these concerns surrounding very seriously, ensuring we monitor the latest research available."
BT pointed to a report from a year ago by the World Health Organisation (WHO), which gave mobile phone and wireless networks a clean bill of health.
"Recent surveys have shown that the RF exposures from base stations range from 0.002% to 2% of the levels of international exposure guidelines, depending on a variety of factors such as the proximity to the antenna and the surrounding environment," said the WHO report. "This is lower or comparable to RF exposures from radio or television broadcast transmitters."
"In fact, due to their lower frequency, at similar RF exposure levels, the body absorbs up to five times more of the signal from FM radio and television than from base stations," it said.
"From all evidence accumulated so far, no adverse short- or long-term health effects have been shown to occur from the RF signals produced by base stations. Since wireless networks produce generally lower RF signals than base stations, no adverse health effects are expected from exposure to them," said the report.
Panorama has talked to scientists sceptical about the safety limits set by governments, and of the research that has shown no ill-effects of mobile phone technology.
There have been up to 3,000 studies of mobile phone technology and its possible health effects but few if any on Wi-Fi networks.