You have raised a good point. Here are the three impotant parameters: 1. radiated power 2. distance from radiator to receptor 3. exposure (time of use)
Radiated power--I am unsure of the standard radiated power of cordless versus cellular phones. Typically cordless phones are designed to work (well) only within 100 feet or so of the base station, while cellulars must work with distant cell antennas. However, the cell antennas may be more sensitive, allowing for lower radiated power at the source. Distance--Most cordless phones have antennas that extend "above" the users head, while small cellulars either have internal or external antenna that are more likely on the same level as and closer proximity to the head. Exposure--From what I observe on the road, parking lots, malls etc., I believe cell phone users spend a LOT more time on their cellphones than I ever spent on my cordless phone. It was never my "default" phone of choice in my home. There was a recent Dateline? or similar show that had to go outside the U.S. to find a firm willing to test cellphones for their radiation levels within a simulated brain. No firm that does this type work for the big cellphone mfrs was going to help in an "expose". The test uses a cavity shaped like a 1/2 of a human skull, as if lying on its side. The cavity is filled with a fluid designed to simulate the brain's viscosity etc. The receiving probe is suspended withn the fluid. The cellphone is held under the cavity in postitions designed to simulate the many ways users hold phones to their heads. Many models were tested. Nearly all failed to meet the stated requirements in at least one position. Some did not meet in any reasonable position. Notable: The best results were obtained with a newer Motorola model that opens to form a 135o or so angle. The result is that the antenna extending from the lower portion is inverted away from the head, moreso than the usual straight-line design. The measured results were very good, again pointing out the importance of the distance involved. If the antenna is viewed as a point source, the power diminishes with the cube of the distance, i.e. 1/d**3. The program pointed out that the standard to be met may or may not be safe, but only addressed actual measurements compared to the standard. George Alspaugh mkelson%[email protected] on 12/01/99 02:10:56 PM Please respond to mkelson%[email protected] To: emc-pstc%[email protected] cc: (bcc: George Alspaugh/Lex/Lexmark) Subject: RE: Cell Phone Hazards? In a follow up to the same article a reader asks: "What about 900+ MHz cordless phones? Are they in the same microwave frequency? They seem to be more common than cell phones, and people tend to talk longer with cordless phones. What's the health risk of those?" I have often been curious about possible health hazards with these also. I do suppose, though, that the amount of power coming from a cordless phone is at least several magnitudes smaller than from a cell phone. Max Kelson Evans & Sutherland --------- This message is coming from the emc-pstc discussion list. To cancel your subscription, send mail to [email protected] with the single line: "unsubscribe emc-pstc" (without the quotes). For help, send mail to [email protected], [email protected], [email protected], or [email protected] (the list administrators).
