NCJ Number
201252
Date Published
2001
Length
5 pages
Annotation
This paper provides an overview of the type of technologies available to screen mail for the detection of mail bombs and possibly other hazardous material.
Abstract
There are four primary types of explosive-detection technology available. These are x-ray machines, which make visible the components that may indicate a bomb; metal detectors, which may help detect the components that indicate a bomb; explosive vapor detectors (EVDs), which detect the vapors from explosives (this also includes explosive-detection dogs); and neutron analysis and similar equipment that detects explosives through atomic signature. The paper advises that each type of technology has advantages and limitations. Given the need for a rapid screening of mail, EVDs, dogs, and atomic analysis are not suitable for such screening; therefore, this paper focuses on the use of metal detectors and x-ray machines. It notes that the ability to see the contents of the mail items is a major factor and advantage in the accurate screening of mail. The use of an x-ray machine or a metal detector in conjunction with an x-ray machine is more effective than the use of a metal detector alone. In large mail handling facilities, the use of a conveyor could reduce the time required to screen mail; in smaller facilities any savings in time must be calculated against the added expense of a conveyor system. The paper cautions that no machine currently available will detect all the possible types of bombs, and they will occasionally make false identifications.