Pilots are already exposed to higher levels of radiation than nearly all professionals because they spend so much time at altitude and receive radiation from space; asking them to take an X-ray every time they get on a plane (even one that the TSA says is thousands of times less intense than a hospital chest X-ray) was asking too much.Popular Mechanics posted more details on pilot exposure.The dose to the skin from one screening would be approximately 0.56 µSv when the effective dose for that same screening would be 0.25 µSv. Brenner, who helped draft guidelines for full-body scanners (but now says he wouldn’t have done it if he knew the scanners would be used in such a widespread fashion), and he wrote back, “We know the radiation dose is very low but there are different views about just how low.
The back-scattering X-rays the TSA uses, however, aren’t like that at all—they penetrate just the clothes and the top layers of skin, and the scanner reads what’s reflected back.Because the full body scanners don’t need to go through your skin, they use less powerful radiation than the X-ray machines in the hospital.Fortunately, Kinesix’s Sammi software has made it possible for Beijing to do just that, offering capabilities that meet very demanding requirements." -"Integrating numerous control functions into a single operational system requires a human-machine interface capable of displaying huge volumes of streaming data across dozens of workstations.Fortunately, Kinesix’s Sammi software has made it possible for Vancouver to do just that, offering capabilities that meet very demanding requirements." -"Because of its ease-of-use and sophisticated graphics, Sammi enables our workstations on the ground to effortlessly process telemetry from our satellites in space.The FDA finally replied with a lengthy letter citing study after study that show full-body scanning is safe, the agency says.
The UCSF profs’ main beef is this: We know the risks of medical chest X-rays, for example, which penetrate the skin to make those pictures of our bones.
When an X-ray Compton scatters, it doesn’t shift an electron to a higher energy level; instead, it hits the electron hard enough to dislodge it from its atom.
The authors note that this process is “likely breaking bonds,” which could cause mutations in cells and raise the risk of cancer.
[Ars Technica] FDA, in its response letter, said: The concern that “the dose to the skin may be dangerously high” is not supported.
The recommended limit for annual dose to the skin for the general public is 50,000 µSv.
Two examples are the BRCA-1 and BRCA-2 mutations associated with breast and ovarian cancer, but scientists believe many more such defects are unknown. I don’t know if you’re one of those 5 percent,” Brenner says, “And we don’t really have a quick and easy test to find those individuals.” [NPR] Furthermore, the UCSF researchers write in their letter, older passengers are more susceptible to mutagenic effects of X-rays, and “the risk of radiation emission to children and adolescents does not appears to have been fully evaluated.” Safer alternative?