Re: an infant got x-rayed
Jack, just to check... did you carry on films, rather than put them in checked luggage? Sensitivity of emulsion to x-ray and that to visible light are determined by rather different mechanisms, and generally speaking, old technology high speed color films are more sensitive to x-ray than modern b&w films. But then x-ray varies a lot. The REM scale commonly used take the difference into account in terms of the "equivalent" biological effects, not equivalent effects to silver halide crystals. So, the real story is more complicated (but no surprise here). I've also posted in the past the same thing as what Jordan said. If you take a roundtrip transatlantic flight, you get about the same dose of radiation as a single chest x-ray. But again this is compared in REM scale... (BTW x-ray imaging of bones use a lot more x-ray. CT-scans use even more.) I used to request hand inspection, but when I learned that not many countries give this right to travelers explicitly (and I too had unplesant experience at Gatwick airpot), I started using lead bag and tell the inspector that my luggage contains specialty photographic equipment and films in thick lead bag, and ask them if they would rather hand inspect. Most of the time they are happy to look at the faint shadow of films for a brief moment and I never had any adverse effect, including T-MAX P3200. At one time the TSA employee told me that the bag cuts the x-ray but he can still count how many rolls I have in the bag. Ryuji From: Jack Fulton <jefulton1@comcast.net> Subject: Re: an infant got x-rayed (was Re: Pablo Picasso's sculptures got x-rayed) Date: Thu, 21 Dec 2006 10:32:35 -0800 > Okay, scanners @ airports. I'm afraid of them and have actually had > film latensified, so to speak by them. > Both were high speed: TMax 400 and Fuji 1600 ISO color neg. Two years > ago, flying to Italy, I sent ALL my > film via FedEx to Italy. The film I took with me was noticeably > fogged. It might have been because I needed > to go through San Francisco x-rays and also the famed RyanAir-no- > compromise inspection in England to > Italy, then back. But, th epoint is that the film indeed, was fogged. > Rather low in contrast ultimately. > Jack F > > > > On December2006, at 9:18 AM, Jordan Wosnick wrote: > > > > > Ryuji, I don't know the details, but I too have often wondered why > > people insist on having slow film hand-inspected rather than > > putting it through the carry-on luggage X-ray scanner. I have never > > actually seen any documented evidence of film being ruined by such > > a scanner. > > > > I've read in the past that film gets exposed to more high-energy > > radiation during a flight (due to increased cosmic ray penetration > > at high altitudes) than it does in a carry-on luggage X-ray > > scanner. I don't know how true this is. > > > > X-ray scanners for checked luggage are a different story, as they > > are much larger and more powerful. > > > > Jordan > > > > Ryuji Suzuki wrote: > > > >> Another curious note is this: > >> In the several seconds the baby spent in the machine, the > >> doctor added, he was exposed to as much radiation as he > >> would naturally get from cosmic rays — or high energy from > >> outer space — in a day. (quoted from LA Times link above) > >> Is this really true? Then what's the point of asking for hand > >> inspection of films? (if it's carried on anyway) The bar graph > >> in the article (as well as the video) indicates that the > >> radiation dose of the x-ray luggage screener is 1 mREM and > >> this indeed is not that much. > > > > > > -- > > > > > > Jordan Wosnick > > jwosnick@fastmail.fm >
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