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FreightWaves Flashback: Customs to X-ray your pallet

1992: 15 machines on order at cost of $130,000 each

Photo: Jim Allen/FreightWaves

FreightWaves Classics articles look at various aspects of the transportation industry’s history. If there are topics that you think would be of interest, please send them to [email protected].

The many industries that make up the world of freight have undergone tremendous change over the past several decades. Each week, FreightWaves explores the archives of American Shipper’s nearly 70-year-old collection of shipping and maritime publications to showcase interesting freight stories of long ago.

In this week’s edition, from the April 1992 issue of American Shipper (virtual page 72), FreightWaves Flashback looks at Customs’ plans to inspect containers in record time.

A CAT scan for your container?


U.S. Customs is contracting with a Cambridge, Massachusetts, company to design and construct an X-ray unit that can examine the cargo inside a standard container in about three minutes.

Present customs inspections are time consuming and labor intensive, taking hours or even days. That has meant time lost and an increased potential of damage to shippers’ cargo. And with a heightened demand for interdiction of smuggled drugs, currency and other contraband, Customs is hoping that the units will provide a cure.

American Science and Engineering Inc. is providing Customs with 15 smaller X-ray units that can handle a full pallet of cargo, to be installed in contraband examination stations at ports throughout the U.S. The company had previously produced 25 mobile X-ray units that could X-ray an area 32 inches wide. They have successfully operated for three years, Customs officials say.

The new X-ray units, called the 101 XL, can scan up to 60 inches, or a fully loaded pallet. The units cost about $130,000 each. Customs has tested a 101 XL in the Port of Seattle since January 1991.


“It’s only had one service call,” said Timothy Markish of Customs’ research and development department. “We’ve only had to make a couple of modifications.”

Within six to nine months, the company will install the Cargo Search II at Customs’ Otay Mesa, California, inspection site at the U.S.-Mexico border. The $3 million to $5 million system will be able to scan empty tanker trucks entering the U.S.

“The only other way to inspect them would be to climb inside with an acetylene torch,” said Dick Sesnewicz, vice president of business development for American Science and Engineering.

Customs and American Science and Engineering anticipate installing similar systems at U.S. ports to search containers and trailers.

Back scatter

American Science and Engineering’s are different from the types used in airport terminals, not only in size but performance.

The units employ a back scatter technology, Sesnewicz said. Horizontal, pencil-thin X-ray beams penetrate through a container or palletized cargo and are reflected back through and analyzed to produce an image. This is an important difference in inspecting steel containers or palletized cargo for contraband.

“Inorganic materials, such as metals, do not absorb X-rays while organic materials do,” Sesnewicz said. A savvy smuggler will pack contraband among computer components, televisions or other metallic materials. If Customs used a standard X-ray unit, the drugs, currency or other contraband would be cloaked from sight as the metals overwhelm the organic matter’s signal.


However, with back scatter technology, the reflected X-rays illuminate the organic contraband with a white glow.

“It makes them show up like gangbusters,” Sesnewicz said.

Just as there are ways for smugglers to beat the standard X-ray system, there are ways to thwart back scatter systems, he said.

“There are ways to beat back scatter, but it’s important not to let the bad guys know how to do that,” he said.

The XL 101 can penetrate the equivalent of about 1.25 inches of steel. That makes the system somewhat limited in scanning densely packed pallets or ones that contain considerable amounts of metal. Cargo System II will be able to penetrate up to 4 inches of steel.

“You can build a high-energy X-ray system that can penetrate 10 inches of steel,” Sesnewicz said. “But to build one that can penetrate more than 4 inches, the cost goes up three or four times. You can get to the point where the technology can’t give return on the money spent.”

Customs selected American Science and Engineering because its systems’ microdose technology does not require the station to be encased in thick or lead-lined walls, Markish said.

The systems have an infinitesimal effect on people and the cargoes scanned, Sesnewicz said.

Inspecting cost

Given the price tag, Customs must make every dollar count. “For the Department of Defense, $3 million to $5 million is a nit on top of a gnat,” Sesnewicz said. “But for Customs that’s a great deal of money.”

Sesnewicz said that Customs can profit by using his company’s X-ray systems. “I think money can be made as well as spent,” he said, citing contraband uncovered, and fines and additional duties assessed, not only for drugs but illegally declared or improperly declared cargo.

“The systems inside the vans have been very effective for breakbulk cargoes,” Markish said. “They’ve more than paid for themselves on currency seizures alone.”

Besides Customs, American Science and Engineering has designed X-ray systems for the Department of State, Secret Service and other customs agencies throughout the world.

Needles in the haystack

While the contraband examination stations aid Customs in its interdiction efforts, officials hope it will save importers time and damage to their cargoes.

“There’s a substantial savings from the way we presently do it,” said Robert Colbert, a Customs inspector in the office of inspection and control. “It’s manpower intensive to open and sometimes damage the freight to make sure there’s no contraband inside.”

Inspections today take from four to six hours, Colbert said. Worse is the amount of time that passes as containers wait for access to the inspection areas, wait to be backed into the bay, unloaded, loaded, sealed and cleared.

Customs estimates that 40% of general inspections are completed within eight hours while 42% take eight to 16 hours; 18% take more than 16 hours.

Intensive inspections can take up to 16 hours for about 40% of the inspections, while 25% take from 16 to 24 hours; 19% can take up to 32 hours, according to Customs, and the rest even longer.

The time inspections take limit the number of inspections Customs makes, which increases the likelihood of contraband slipping through.

“We have to narrow our focus from the grand haystack of all customers,” Colbert said. “Close to 5% of all inbound sea containers are inspected, and we’re only able to do that because of good targeting techniques.” At 8 million inbound containers a year, that amounts to about 400,000 inspections at U.S. ports.

Customs estimates that the pallet-size systems can inspect a container load of cargo in under an hour. Sesnewicz said the system designed for Otay Mesa can scan a container in about three minutes.

Customs has also set some guidelines for shippers to ease the time and potential for damage created by inspections.

Colbert stressed that shippers should palletize cargo in containers to allow them to be unloaded by forklift rather than by hand. 

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