If you’ve been watching pilot unions tell their members to decline to go through the body scanner when they go through security, you’re probably feeling concerned about your safety as well, right? The good news is that there don’t appear to be any real safety implications for the casual traveler and it’s unlikely to be problematic for pilots either. My guess is that this is more of a backlash against the Transportation Security Administration (TSA) rules than anything else. While there are plenty of privacy and annoyance factors to consider, it seems like safety isn’t a major concern.
Much of this has to stem from recent TSA moves. Now, if you are at a checkpoint where there is a backscatter, full body scanner and you are asked to go through it, you have the right to say no. If you say no, however, then you will be subject to a full body massage. The TSA has recently changed the pat-down procedure so that the front of the hand will be used instead of the back and the hands may wander closer to, uh, sensitive areas. In other words, go ahead and turn down the body scan but you’ll then be groped. It’s not a great option.
Pilot unions have now come out saying that their members should avoid body scanners, or what is now being referred to as Advanced Imaging Technology (AIT), due to concerns about radiation. This is an x-ray machine, after all. Captain Dave Bates, president of Allied Pilots Association which represents American’s pilots, says in a letter that pilots should decline the AIT and instead opt for a pat-down. He then says it’s unprofessional to receive a pat-down in public in uniform so pilots should ask for a private screening. If that means that the pilot is unable to be ready to fly on time, then that’s ok. Safety first.
Now Mike Cleary, head of the US Airline Pilots Association at US Airways, has taken it even further. He says that crewmembers should have a witness with them during the pat-down process. After that, pilots need to “evaluate their fitness for duty. As has been determined, there is a wide range of possibilities once you submit to a private screening, and the results can be devastating.”
This is obviously turning into a huge issue, but why? The pilots say that the issue is due to radiation exposure, but much of this seems to be primarily an objection to pilots being subjected to screening at all. The pilots have long argued, and rightly-so in my opinion, that screening on-duty pilots is ridiculous. After all, they are the ones with the locked cockpit door behind them. If they want to do damage, they don’t need to smuggle something on the plane to do it. They control the plane. There are issues with ensuring that someone is actually a pilot and that they are on-duty, but those are solvable. Flying pilots shouldn’t need to be screened, so now the unions are, in my opinion, putting out these directives in order to try to bring some urgency to the issue.
But should you be concerned about your own safety here from radiation? I don’t think so. The Food and Drug Administration (FDA) has put out a lengthy letter to the University of California regarding concerns stated by Dr John Holdren about the potentially harmful effects of these machines. I’ve read through the letter and I’d say I understand half of it at best. So maybe smarter people than I can help translate, but I get the main points of it. As Kai Ryssdal says, let’s do the numbers.
The established standard for radiation exposure for the general public from man-made, non-medical sources is 1,000 µSv (microsieverts) per year. One microsievert is one millionth of a sievert, and if you’re familiar with the now-outdated measure of rem, a sievert is 1/100 of a rem, so these are tiny little numbers.
Since it’s not possible to control all sources of radiation exposure, the general rule is to try to keep it under 250 µSv per year from sources that can be controlled. For a radiation-emitting machine to be considered “general use,” as the backscatter machines are required to be by TSA, it has to emit 1,000 times less than the 250 µSv limit for each use, or 0.25 µSv. The backscatter machines have passed that in every test. In fact, it appears that the machines actually emit 0.05 µSv per use. That means that a person could go through the machine 13 times a day for every day of the year and still not have exceeded the limit.
But there was also concern that since the exposure is primarily focused on the skin, that could be a problem area even if the general exposure was not. According to the letter, the annual dose limit for skin exposure is 50,000 µSv per year. Even if the machines emitted the required 0.25 µSv (higher than what it actually is), it would take nearly 250 exposures per day to reach the skin limit. That doesn’t appear to be a problem.
Pilots are unhappy because they already face higher doses of radiation from constantly flying. The higher altitude for longer periods of time means more exposure. The FAA estimates that someone flying 1,000 block hours between DC and LA at 35,000 feet in a year would receive a dose of 5,000 µSv. Let’s say that means the person took 200 flights (at an average block time of 5 hours). If he had to go through the AIT each time, it would add only 10 µSv, a downright tiny number in the scheme of things.
Bottom line? If pilots are really concerned about radiation exposure, they should stop flying. The additional amount from the AIT machines is negligible when compared to what they get while in the air.
And remember, if you’re taking a couple trips to year to see grandma, the exposure is truly almost nothing. The exposure to radiation, I mean. The exposure to TSA agents resulting in humiliation is a whole different story.
