Screeling wrote:
Sasandra wrote:
Well if people think they are not "safe" then they should not fly in the first place as the flight itself is far less "safe" and exposes you to significantly more radiation than the backscatter based scanners, also you should not use a cell if you are concerned with health issues either because cell phone use will cause more health issues than the body scanners in the airports would.
Can you explain this? To my knowledge, cell phones don't operate a frequency with a high enough energy to damage cells. Do these scanners operate a lower frequency? If they'r X-ray then they obviously don't.
Cell phones emit a high strength signal and studies have shown that that combined combined to the proximity to the phone to your brain when in use plus the frequency of use causes an increased risk for brain cancer, just like x-ray radiation can. The millimeter wave based systems operate on a much higher frequency than cell phones, millimeter wave is 30-300Ghz, cell phones are in the 700-2500Mhz range so the millimeter wave based systems have very low penetration into any object, plus the signal strength is about 10,000 times less than that of a cell phone as the signal only needs to travel a few feet, not posibly miles thru random objects in the way.
Backscatter based systems also have very little penetration into the body for that matter, they don't work like what most people thing of when they think x-rays, standard x-rays like what you get at your doctor or dentist penetrate thru your body and come out the other side and the exiting x-ray strength is picked up by detectors (or x-ray film typically for your dentist) on the far side to create the x-ray image, backscatter based systems are just strong enough to penetrate clothing and x-rays are bounced back at the x-ray source where there are detectors that pick up the x-rays scatter back to create the image, they are also far more effective at detecting plastic and organics are they scatter x-rays more than absorbing them.
For reference a backscatter based system exposes you to .01 mrem of radiation, you receive 26 mrem annually from cosmic radiation at sea level, 23-90 mrem from terrestrial radiation depending on where in the US you live, 40 mrem from food/water you consume amd 200 mrem from the air you breath.
Do you wear an LCD wrist watch? that's .06 mrem
How about porcelain crowns or false teeth? that's .07 mrem
Do you live in a stone, brick or concrete building? that's good for 7 mrem a year
Considering most people only fly a couple times a year at most you are probably getting more radiation from your dental work and watch than you are from a backscatter based scanner.