The newspaper Web site SheffieldToday.co.uk recently carried an article with comments from Professor Tony Barker at Royal Hallamshire Hospital in the United Kingdom. Professor Barker, who has spent 30 years researching the biological effects of electromagnetic fields, said he has found no evidence to suggest, "mobile phone masts or handsets are a health hazard."
The article, Expert rejects phone mast fear quotes Professor Barker saying there are big TV and broadcast radio transmitters all around us, emitting up to 500,000 watts, 10,000 times more power than a typical 50 watt cellular base station. (U.S. TV broadcast transmitters can operate at effective radiated powers of up to 5 million watts.)
Barker also mentions an issue that many local cell phone tower opponents miss. Cell phones adjust their power level depending on how well the signal is received at the base station. If the base station is closer, then transmit power from the cell phone is reduced to save battery life. Professor Barker explained that because cell phones are closer to the head, "the signals passing into the body from a handset are usually one-thousand to one-million times stronger than those from a base station." Consequently, cell phone users in areas without nearby base stations not only have difficulty maintaining a cell phone connection, but they expose themselves to more RF radiation from their cell phones.
Most of the information in the article is common sense to RF engineers, but the short piece makes for interesting reading. Broadcasters may be comforted by the acceptance of powerful TV transmitters, but as evidenced in Denver, some residents are often as concerned about RF exposure from these transmitters as they are from cellular base stations.
