Global Security Newswire

Some experts believe that the radiation detectors used at U.S. ports and border crossings to detect the possible smuggling of nuclear materials into the United States are ineffective and too prone to nuisance alarms, Newsday reported today (see GSN, May 13).

The radiation portal monitors are pillar-like arrays through which trucks and shipping containers pass to be scanned, according to Newsday. While the detectors scan for gamma rays and neutrons, experts have said that they are not likely to detect weapon-grade radioactive material stored in a well-shielded container.

In addition, the detectors are prone to giving off nuisance alarms when the devices pick up low amounts of radiation, Newsday reported. One U.S. radiation detection expert said that inspectors using the detectors are “definitely getting nuisance alarms regularly.” The detectors have a rate of about one alarm per several thousands vehicles and containers, the expert said.

A Stanford University group found last year that with all aspects of port security, including radiation detectors, there is less than a 10-percent chance of border and customs inspectors detecting a shielded nuclear weapon transported by an unknown carrier, Newsday reported. For a certified shipper, the chances of detecting the smuggled weapon increased to 24 percent, Newsday reported (Earl Lane, Newsday, Aug. 17).