Airports will Test for Liquid Explosives; New Bottle-Screening Technology to be in Major Airports this Summer

New technology that screens bottles for liquid explosives is coming to the nation's busiest airports this summer, the Transportation Security Administration said Tuesday.

The agency plans to deploy 200 machines at airports to detect a certain explosive in the containers passengers are allowed to bring through security checkpoints.

However, the $20,000 PaxPoint machine made by ICx Technologies does not find all explosives, company marketing director Bruce Cumming said.

"It's designed to detect a very specific type of liquid threat that is found in common household liquids," he said.

The machine aims to address concerns raised in August when authorities foiled an alleged plot to bomb U.S.-bound airplanes using liquid bombs, the TSA said.

The handheld machines will not ease restrictions that limit passengers to carrying small containers of liquids and gels on board aircraft, TSA spokeswoman Ellen Howe said. They will primarily check bottles holding medicines, baby formula and other items that passengers can carry on board in unlimited quantities.

"It may not necessarily mean any specific benefit to the traveling public other than enhanced security," Howe said.

A sniffer is held an inch from a container to draw in vapors. An attached sensor displays the level of explosive material in the vapors.

An ICx competitor questioned whether the machine could sense explosives through thick or tightly sealed containers. "If you don't have anything that emits a vapor, then you don't have a trace of a flammable or explosive liquid that it could detect," said Jerry Sellman, president of Sellex International. His company's microwave machine analyzes a liquid's molecular structure to spot explosives.

Mark Prather, ICx's explosives-detection manager, said the PaxPoint is very sensitive and can detect explosives through thick glass, plastic and metal.

The TSA began testing the machines last month at Miami, Newark, Detroit, Los Angeles and Las Vegas airports. A four-week test begins today at Boston's Logan International Airport. Although tests are ongoing, TSA announced its plan to buy 200 of them because "results have shown it is effective," Howe said.

The announcement came as another Homeland Security Department agency said its own effort to find readily available technology that can screen for liquid explosives had failed. The Science and Technology division in September had asked companies to propose "off-the-shelf" technology that could be tested in airports to screen containers for liquids.

The division has decided to solicit ideas for liquid-explosives detectors that will take a year or two to develop, said Douglas Bauer, a Science and Technology explosives-detection expert.