Re: an infant got x-rayed
On December2006, at 10:53 AM, Ryuji Suzuki wrote:
Jack, just to check... did you carry on films, rather than put
them in checked luggage?
Yes. I had also written to Fuji, and they responded with a letter
explaining
how the film could be damaged, and had my Faculty ID, all to no avail.
I had deliberately not used the lead bags but my colleague Linda Connor
does all the time as she works solely with 810 b/w film and travels a
lot.
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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