At the Port of Seattle, the way Customs and Border Protection officers see it, everything that comes in could be a serious threat.

"After 9-11 our mission changed dramatically," says Traci Fukuhara who is with the Port of Seattle.

Fukuhara and CBP Captain Doug McBride gave us special access to a highly-restricted area and found new radiation screeners used here - will soon be used just about everywhere - from our borders to ferries to airports.

"The latest one we are using is a mobile radiation portal monitoring trucks," says Fukuhara.

At the port: these two mobile radiation portal monitoring trucks or RPMs can be positioned just about anywhere and they are so sensitive:

"The machine will detect not only what's in a container, but it will detect any type of radiation treatment that the driver may have had," adds Fukuhara.

Those mobile units do a preliminary check for radiation, but if they notice a problem then officers use a hand held device to scan for hotspots. That information is then loaded to a data base and scientists can read is right away.

It's the same technology and equipment just installed at Friday Harbor. This time not just for cargo, but trucks and cars, anyone trying to drive off.

"In the very near future it will be tested at Sea-Tac International Airport and will screen passengers and their baggage.

That's what international travelers can expect through a pilot program starting next month, but an important note: those radiation screeners only detect radiation.

"It is a passive device. It doesn't emit radiation," explains Fukuhara.

"This container came through and set off the alert," warns CBP Officer Scott Miller as he walks over to the truck and picks up one of the hand-held scanning devices. He's had to go through this step a dozen times already today. "It's a constant stream of cargo at the port. On this day: picking up radiation from some electronic equipment on board that container.

And, that's not the only thing that triggers a warning:

"Everyday items, granite, counter tops, marble, toilets, bananas," Miller continues.

It's a serious system now sensing danger around you.

"This is something that's necessary to protect public," Fukuhara reminds us.

This new radiation screening system at Friday Harbor and coming soon to Sea-Tac, uses what's called "passive or non-intrusive" technology. So again, it does not emit radiation it just detects it.

Still, the machine is so sensitive officers are telling any travelers: If you've had radiation treatment recently, carry documents to verify that.