Why is frisking done at airports even when x-ray machines are present?
The door metal detector is not an X-ray machine. Only your bags go through the X-ray machine. If the door WAS an X-ray machine there would be a lot of dead passengers because X-rays cause cancer. They frisk you with a smaller metal detector so they know exactly where the metal is since the door only shows that a particular person has metal. Nonmetallic things could include plastic guns, toxic chemicals, etc.
Door frame metal detector could detect presence of the metal only to some extent.Hand held metal detector can even find a metal plate inserted into the bone and it is used to have an intensive and accurate search.Strictly speaking frisking the body is to find not only dangerous substances but also to detect legally prohibited substances such as narcotics.
