Three are already in service, one in California and two in New Mexico. Well, north of El Paso, TX, which is close enough. And which I'll have to drive through whenever I go to El Paso, unless I take 150 mile detour through Las Cruces.
I definitely don't like this. This is ionizing radiation, which can damage tissue and DNA, and it's powerful enough to image through a metal car. DHS, of course, says it's perfectly safe. But we don't have studies approved by the FDA saying yea or nay. If your car were to stall with you in the middle of the scanner, you get an increased radiation dose. You know they're not going to build a mechanism like a self-service car wash where the machine moves around you, which would have the same risk, it's just not viable and slows checkpoint throughput. And they're not going to give an option for you to get out of your car and a DHS person drives your car through it, that increases their liability if your car gets damaged. So you're going to have to drive your car through it, no opt-out.
I asked an officer at the checkpoint between Las Cruces and Alamogordo about their backscatter x-ray van. It was late at night, no traffic behind me, and it had been gone for a while so I commented that it was back. The officer was surprised that I knew anything about it. I asked him how often they used it, and he said only occasionally, so I assume they use it for suspicious vehicles and 18-wheelers. The question is whether or not this drive-through thing is compulsory for all or just for suspicious vehicles.
I also feel more than a little sympathy for the officers at the checkpoints. These are ionizing radiation devices that the only statement of safety is the manufacturer and their employer, no independent third-party or government agency. I doubt the officers are going to be issued dosimeters to monitor their radiation exposure, though TSA has put out an RFP for quotes for dosimeters for airport security check workers (we'll see if that actually happens). There was a cancer cluster at Logan Airport in Boston among workers x-raying baggage, I haven't heard of anything yet with airport checkpoint workers.
It's definitely time for me to once again write my congresscritters.http://news.cnet.com/8301-31921_3-57358146-281/dhs-x-ray-scanners-could-be-cancer-risk-to-border-crossers/