Wireless networks - known as wi-fi or wLAN (wireless local area network) - are increasingly used in schools, offices and other public places to connect computers and laptops to the internet using radiofrequency transmitters with no need for complex cabling. In future, whole town centres will be transformed into wi-fi hot spots." It has taken the public a while to wake up to the idea that wireless transmitters could be less than benign. The groundswell of concern is mounting, with some people blaming everything from headaches to cancer on exposure to radio-frequency fields. A number of schools have dismantled their wireless networks after lobbying from worried parents, and others are under pressure to follow suit. In Austria the public health department of Salzburg has advised schools and kindergartens not to use wLAN or cordless phones. Lakehead University in Ontario, Canada, which has 7,400 students, has removed wi-fi because of what its Vice-Chancellor, Dr Fred Gilbert, calls "the weight of evidence demonstrating behavioural effects and physiological impacts at the tissue, cellular and cell level". Some experts have also expressed concerns. In September, 30 scientists from all over the world signed a resolution calling for a "full and independent review of the scientific evidence that points to hazards from current electromagnetic field exposure conditions worldwide."