The Transportation Security Administration (TSA) is partnering with Amtrak to test new security technology that can help officials detect whether an individual is concealing an improvised explosive device such as a suicide vest. The testing of the equipment is taking place inside New York’s Pennsylvania Station in the Amtrak concourse section of the station.

The passive system, known as a stand-off explosive detection unit, triggers an alarm if an individual carrying/wearing a person-borne improvised explosive device (PBIED) passes by the mechanism. It is a type of screening technology that can be used by Amtrak and mass transit agencies to detect potential threats — metallic or non-metallic — by identifying objects that block the naturally-occurring emissions emitted by a person’s body. No radiation of any kind is emitted by the unit, and no anatomical details of a person are displayed. The operator of the equipment sees either a green image of a person, known as a “green ghost,” alongside of the actual image of the individual or a color-indicator bar overlay, depending on which model of the technology is being used.

The use of such a device enables a rail or transit agency to help safeguard against terrorist threats in the mass transit environment. It is operated by employees of the agency, not by TSA. TSA is, however, supplying two models of the equipment for the purposes of the demonstration. One model is mounted on a tripod and another is contained in a trunk.

The equipment is mobile, which allows agencies to easily relocate it to different stations. Users operate it via a laptop computer in the station. The image that appears on the laptop reveals concealed objects that block naturally occurring body emissions and indicate the location and size of those objects on a green image of an individual.

TSA has been working with several passenger rail and transit agencies as test beds on demonstrations of this type of security equipment, including Amtrak, New Jersey Transit, the San Francisco Bay Area Rapid Transit District, the Los Angeles Sheriff’s Department and the Los Angeles Metropolitan Transit Authority.