Liquid explosive detectors.

• Position: Miss

[ILLUSTRATION OMITTED]

* Two years after London authorities thwarted a terrorist plot to blow up transatlantic airliners by using liquid explosives, passengers still are banned from carrying water bottles onto planes. The reason? A lack of explosives detection technologies that allow security officers to screen liquids inside carry-on bags.

The silver bullet technology has not yet materialized for the Transportation Security Administration to withdraw its "3-1-1" policy, which limits the amount of liquid-based products that can be brought through the passenger checkpoint.

But the government is testing several detection systems and investing in those that pass muster. One of them is a handheld bottled liquid scanner called the Fido PaxPoint, made by ICX Technologies. The unit works by detecting vapors emanating from a container. It can be used at checkpoints to test explosive liquids, or for...