Port security: a novel cargo scanner

One of the biggest problems in guarding America's borders is screening all the cargo that comes into or goes out of America’s ports. I checked and some container ships can carry 15,000 of those ubiquitous 53’ long containers and most of the ships are unloaded in <18 hours and much of the cargo must immediately be put on trucks or trains an sent to their final destination. The port of LA, alone handles nearly 4 million containers a year, so the volume of goods staggering. How then do you check every container for illegal or other questionable items? Visual inspection is out since there isn’t time or resources. Some people have suggested that each container be scanned with terahertz waves (think super-radar) or back scattered X-rays (which are gentle and safe-ish.) Both of these solutions require the cargo to be on a truck and hold still for minutes at a time to be scanned, so they are also difficult to deploy. My idea is different, I suggest making those massive gantry cranes that load and unload the ships into sensor platforms. Here is how it would work: When the containers are picked up they deflect (twist under their own weight) which causes them to breath out and in. So by mounting a radiological, biological and chemical sensor platform on the edges of the spreader bar where it can sample this air, every container can be inspected. The air in the containers enriches itself for the chemical signature of the contents during transport, and the containers are reinforced while on the ship to reduce deflection, so turn over of air during shipping is minimal. Since every container goes on and comes off the ship in a set order and the contents are documented, if a container “needs” additional inspection the sensor platform can radio the customs official, or perhaps every container gets an encrypted write once RFID tag, which is scanned as the containers leave the port. Since some cargo will be things we need to watch, but might actually be ok, the platform can save a record of what it scanned for further analysis, like those filter pads at the airport, on a time stamped spool or something. Then at the shift change of the crane operator the Customs or other HLS official can change it out, and send it to a lab for analysis. A crane mounted sensor platform will not reduce the need for visual inspections but will help better identify containers, which might be suspect, so resources could be better utilized. Better still the idea can be sold to the ports and shipping companies as a way to speed up the processing of cargo as well as identify cargo that has spoiled, broken or been tampered with during shipping.