flying, film and X-rays

"nobody" wrote in message
...
Craig wrote:

It is best to arrive at the inspection point with all rolls out of the
boxes
and canisters in a ziplok bag. Make it easy for them to do a very fast
hand inspection.

Absolutely the most important point - do all you can to make it easier for
them to do what you want them to do. Taking the film out of the boxes and
out of the cans and placing them in clear plastic bags to pretty much
mandatory if you hope to have hand inspection outside the US.

For those cases where they refuse, you cfan then take the ziplok and put
in it
a lead bag and allow it through the x-ray. (Some say that they will just
increase the power to see through it, but I am not sure if this is true or
just urban myth).

Urban myth. It used to be true, but the technology has change while the
story hasn't. The gate security x-ray machines IN THE US are pulsed - they
work like an electronic flash that uses x-rays instead of visible light. It
captures a snapshot to the video display on the system. These machines use
this method to reduce the amount of x-rays required to get a useful image so
as to minimize the weight of the machines. Now that they are needed in
large numbers, the old continuous beam types would place more weight in a
limited area (because of the shielding required) than most structures can
support. It was those older types that allowed the operator to raised the
intensity of the x-ray beam, something that was counter to the shielding
designed to minimize exposure of the security staff.

Exit trivia mode.

But, having raised the subject - it is more important to do your best to get
hand inspection outside the US. We pushed countries around the world to
increase airport security and helped them do it by giving them the old,
continuous beam x-ray machines we replaced with our new flash-types. So you
can expect to encounter stronger x-rays if you travel outside the US,
western Europe, and Japan. This puts more importance on arranging your film
in an easy-to-inspect configuration and asking very nicely (outside the US
you have no rights), and letting them know your are concerned about the
cumulative effect of all the x-rays on your ROUND TRIP.

And be sure to allow yourself enough time. You have a right under FAA rules
to request hand inspection, but there are no specifications about how fast
it has to get done. So irritating the security staff isn't in your best
ineterst, nor is hiding the film in canisters or boxes. Getting hand
inspection, avoiding the x-ray exposure, and missing your plane won't make
for memorable trip. Actually, it will, but not the kind most folks try for.

It will also help to mention that you are taking a large number flights
and
that while just one x-ray exposure may be ok, in your case, you need to
reduce
the cumulative effects.

And, if you haven't heard or read, NEVER NEVER NEVER put your film into a
checked-in bag. All checked luggage gets a CT scan in all US airports now -
there's no escaping it, and it will fog your film, even the slower stuff.

Bob in Las Vegas

Bob-
Interesting input older x-ray machines, specifically the user's ability
to "adjust" them. Can you be more specific?
I've worked on a number of early 80's vintage PerkinElmer x-ray machines in
airports, but have never seen one that was adjustable
"on-the-fly".
And I suppose you can say they are "pulsed", in that items are x-rayed in
"slices" and the images are assembled by
video boards ( or nowadays, the computer inside ), and the image moves
across the monitor to coincide with the movement of the belt.
Cheers.
LH

"JRF" wrote in message
news:OLlTb.16511$tP1.7787@fed1read07...
"nobody" wrote in message
...
Craig wrote:

It is best to arrive at the inspection point with all rolls out of the
boxes
and canisters in a ziplok bag. Make it easy for them to do a very fast
hand inspection.

Absolutely the most important point - do all you can to make it easier for
them to do what you want them to do. Taking the film out of the boxes and
out of the cans and placing them in clear plastic bags to pretty much
mandatory if you hope to have hand inspection outside the US.

For those cases where they refuse, you cfan then take the ziplok and put
in it
a lead bag and allow it through the x-ray. (Some say that they will just
increase the power to see through it, but I am not sure if this is true
or
just urban myth).

Urban myth. It used to be true, but the technology has change while the
story hasn't. The gate security x-ray machines IN THE US are pulsed -
they
work like an electronic flash that uses x-rays instead of visible light.
It
captures a snapshot to the video display on the system. These machines
use
this method to reduce the amount of x-rays required to get a useful image
so
as to minimize the weight of the machines. Now that they are needed in
large numbers, the old continuous beam types would place more weight in a
limited area (because of the shielding required) than most structures can
support. It was those older types that allowed the operator to raised the
intensity of the x-ray beam, something that was counter to the shielding
designed to minimize exposure of the security staff.

Exit trivia mode.

But, having raised the subject - it is more important to do your best to
get
hand inspection outside the US. We pushed countries around the world to
increase airport security and helped them do it by giving them the old,
continuous beam x-ray machines we replaced with our new flash-types. So
you
can expect to encounter stronger x-rays if you travel outside the US,
western Europe, and Japan. This puts more importance on arranging your
film
in an easy-to-inspect configuration and asking very nicely (outside the US
you have no rights), and letting them know your are concerned about the
cumulative effect of all the x-rays on your ROUND TRIP.

And be sure to allow yourself enough time. You have a right under FAA
rules
to request hand inspection, but there are no specifications about how fast
it has to get done. So irritating the security staff isn't in your best
ineterst, nor is hiding the film in canisters or boxes. Getting hand
inspection, avoiding the x-ray exposure, and missing your plane won't make
for memorable trip. Actually, it will, but not the kind most folks try
for.

It will also help to mention that you are taking a large number flights
and
that while just one x-ray exposure may be ok, in your case, you need to
reduce
the cumulative effects.

And, if you haven't heard or read, NEVER NEVER NEVER put your film into a
checked-in bag. All checked luggage gets a CT scan in all US airports
now -
there's no escaping it, and it will fog your film, even the slower stuff.

Bob in Las Vegas

JRF wrote:

"nobody" wrote in message
...

Craig wrote:

It is best to arrive at the inspection point with all rolls out of the

boxes

and canisters in a ziplok bag. Make it easy for them to do a very fast

hand inspection.



I've flown once with film and requested a hand inspection. In the US,
they looked at me like I was nuts. They then allowed me stand in their
secondary inspection lane for about 40 minutes while they did everything
else they could before inspecting my film. They did the swipe with each
individual roll. Then they did re-reviewed me. X-rayed shoes, pat down
and all that.

On the return through CDG, they just told me to put in the machine. End
of story.

"Lester Higgins" wrote in message
ink.net...
Bob-
Interesting input older x-ray machines, specifically the user's
ability
to "adjust" them. Can you be more specific?
I've worked on a number of early 80's vintage PerkinElmer x-ray machines
in
airports, but have never seen one that was adjustable
"on-the-fly".

Over the years there have been security x-rays by Perkin-Elmer, Pickering,
and others (even General Electric long ago), and the features were not the
same on all these gizmos. Some had a rheostat for adjusting voltage to the
x-ray tube, which allowed the operator to increase the energy of the x-rays,
and that is the characteristic that determines how well the x-rays
penetrate. Unfortunately, when the powered-up x-rays were penetrating the
bag more effectively, they were also penetrating thru the shielding around
the machine, too. The traveling public wasn't really affected - none were
present around the machines long enough to get a meaningful exposure. But
the guards who were there 40 hours a week got higher doses than planned.

There was another effect. Ramping up the voltage (and those tubes run in
the 70,000 to 100,000 volt range) also ramped up the heat generated and thus
the wear and tear on the tube. Turning it up too fast also strained the
tube and tended to shorten its life expectancy.

The adjustable machines weren't used everywhere - there was no effort in
those days to standardize the hardware or the detection capability. And
your experience is probably more typical of what was available in the more
significant airports. The adjustable machines I saw were only in
backwater-types - Muscle Shoals, Alabama and Rapid City, South Dakota are
the two I remember specifically.

And I suppose you can say they are "pulsed", in that items are x-rayed in
"slices" and the images are assembled by
video boards ( or nowadays, the computer inside ), and the image moves
across the monitor to coincide with the movement of the belt.

The gate security machines used by the TSA now are powered by a capacitive
discharge-type tube that is truly a pulsed device. The flash duration is in
the same neighborhood as an average electronic flash. The operator can take
images in rapid succession, but there isn't a true continuous display of a
moving image.

The slices you talk of are the CT scan technology used for checked luggage.
The narrowly focused x-rays pass thru the bag in slices that generate planar
images that are assembled in a computer to approximate a three-dimensional
image of the contents without opening the bag. Pretty cool way to do
business, IMHO.

I have to deal with these devices routinely because I run a radiation
dosimetry program. The dosimeters are used to measure work-related dose
from radiation like x-rays, among others. I have people who take dosimeters
with them when they travel, and I'm constantly reminding them to take them
in their carry-on because the exposure of the dosimeter is unmeasurably
small, while the CT scan of checked luggage blows them away (not in the
sense of damaging the dosimeter but delivering a dose so large that the
dosimeter becomes useless for determining that person's occupational dose).

Probably more than anyone want to know (TMI).

Bob in Las Vegas