Is metal detector a different thing from full body scanner?
In Russia they have installed metal detectors (I believe) on entrance to suburban and subway train stations. Of course, with the huge amount of traffic the police officers simply cannot inspect every person who rings positive, so they just ignore the detector altogether.
"Backscatter X-ray is an advanced X-ray imaging technology. Traditional X-ray machines detect hard and soft materials by the variation in transmission through the target. In contrast, backscatter X-ray detects the radiation that reflects from the target. It has potential applications where less-destructive examination is required, and can be used if only one side of the target is available for examination." from Wikipedia. http://en.wikipedia.org/wiki/Backscatter_X-ray
In Russia they have installed metal detectors (I believe) on entrance to suburban and subway train stations. Of course, with the huge amount of traffic the police officers simply cannot inspect every person who rings positive, so they just ignore the detector altogether.