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One of the searchers, "Becky" (she asked that her real name not be used), described how she made her rounds on a recent training exercise in a large city. A 31-year-old Energy Department employee who began training as a nest searcher seven years ago, Becky and 10 colleagues were assigned to hunt for a simulated nuclear device in a hotel with 32 floors and 2,052 rooms.
Walking down the corridors, Becky and her male partner looked like the typical tourist couple on vacation, dressed in Bermuda shorts and T shirts, cameras slung over their necks. But hidden in Becky's suitcase was a sophisticated sodium iodide crystal detector to sniff minute amounts of gamma radiation from as far away as another room.
Halfway down a corridor, Becky suddenly heard "the voice," an irritating robotic message transmitted from the suitcase to a wireless, button-sized beige receiver in her ear. "Gamma alarm four," the voice droned. That was a strong radiation signal. She glanced left at the room number on the next door and subtracted three from it. The detector's microcomputer takes several seconds to analyze the radiation and calculate its strength, so the room three doors behind her must have been the one actually giving off gamma rays.
Becky and her partner never turned around or slowed their pace, lest they attract attention from other guests. At the end of the corridor, they looked back nonchalantly, then ducked into the stairwell. Becky pulled out a small radio from her purse. "We have a hit," she whispered, and relayed the room number. The searchers had found the simulated nuclear device, which had been emitting a harmless amount of radiation, in less than two hours.
As if the searching weren't nerve-racking enough, operating the detectors requires great skill because the instruments, sensitive enough to home in on a bomb, can be confused by the soup of a metropolis' naturally occurring radiation. Freshly paved roads, yellow rest-room tiles, the Vermont granite used in some of Washington's federal buildings, a patient walking out of a hospital after radiation therapy, even a bunch of bananas can set off the detectors. Finding a nuclear bomb in a city, according to a searcher, "is like looking for a needle in a haystack of needles."
Though NEST has yet to find a nuclear device, the team has unearthed conventional bombs. The only case involving nuclear material involved an employee at a Wilmington, North Carolina, nuclear fuel plant who stole a small amount of low-grade uranium and threatened to disperse it. The fbi quickly recovered the uranium, and NEST didn't have to be summoned.
In case a real nuclear device ever is found, NEST's diagnostic and assessment teams have all kinds of equipment, such as portable X-ray machines, with which to peek under the bomb's wrapping. An instrument that looks like a Dustbuster is swept over the outside of the bomb to vacuum up any faint but telling fumes it might emit.