Some have speculated that prolonged exposure to wireless network devices could cause memory loss or other brain damage. However, potential health hazards from the microwave signals of WLANs have not been validated scientifically. In fact, using a WLAN is most likely much safer than using a cell phone.
Why? A typical home wireless network transmits radio signals in the same general frequency range as microwave ovens. Yet compared to ovens and even cell phones, wireless network cards and access points transmit at very low power, anywhere from 100 to 1000 times less. In addition, WLANs send radio signals only intermittently, during data transmisssion, whereas cell phones transmit continously while powered on. Overall, the cumulative exposure to microwave radiation from a WLAN remains much, much less than exposure from other radio frequency devices.