Airport Scanners - the age old question (finally somewhat settled)

[BrianShaw]

I am not being argumentative, I am actually responding to the arguments people are making against my statements.

Since you are not saying it is impossible to have film damaged by the carry on scanners, I think you are in the minority here. And then you are also not really disagreeing with me, so I was mistaken to take your posts as those who are.

The only thing I can think about why that one roll was damaged is that they all were not in the same place in my bag. They were spread out in different pockets.

I don't think the person was being malicious. He was annoyed that no one was coming to do his "bag check" so he kept moving things around on the screen, moving it back and forth, re-looking at it again, all the while yelling "bag check" about 25 times to no avail. I actually think he was annoyed to not be able to continue to put other luggage through the screener while he waited, but it appears that is their protocol.

I will be requesting hand checks. I could tell you the story about when I did it and was refused in Austin and then reported the person to the supervisor... but then again, I don't want to start up a whole other problem on this thread.

I can't speak for the others so let me speak for myself. I NEVER said "impossible", but I did say "unlikely".

I've understand the "bag check" scenario completely. Been there many times, and been behind people in that situation many times too. Generally, IN MY EXPERIENCE, the screeners sit there with their thumbs up their @$$ while repeatedly screaming "bag check" rather than diddling with their machine.

I, too, a long time ago asked for hand checks and have been refused -- in both US and foriegn countries. Given little or no option I started putting film through the scanners and not worrying about it. Never had a problem, but I generally shoot <200 ASA film and seldom accrue more than 4 screenings on that film. If I have film that has been screened 4 times but not exposed, I don't take it with me on air travel or I throw it out. (Maybe I should start selling it like Petrino does. )

Good luck to you in your future travels.

[rdenney]

Really? So you think they are saying it is ok to put it through the checked baggage scanner fewer than six times and only request a hand check for the sixth time? Because that's what your read of this implies.

If that's what you got from what I said, then your ability to read receives a further challenge.

The Kodak report applies only to the scanners used for checked bags. As I said, the conclusion I draw from it is to carry film through the security line and never put it in checked bags. I thought this was settled knowledge in any case.

The question is why you refute a discussion about the scanners in the security line with a report about the (very different) scanners used for checked bags?

Rick "who never puts film in checked baggage--ever" Denney

[Jim Michael]

It's really very simple. X-ray exposure, like any exposure, is cumulative. At some number of trips through a scanner a threshold will be crossed and density will be registered in the film. There may be other factors at play influencing exposure, such as the orientation of the film WRT the source, objects in the path that are capable of attenuating X-radiation, etc. Any other prior exposure counts too.

[E. von Hoegh]

I'd like to know the precise amount of X-ray exposure at each airport, so I can arrive in Europe with my B&W film properly pre-exposed. I want the maximum shadow detail in my photos of cathedral interiors at night.

[GPS]

Make it 2x SF-NY, +1N

[John NYC]

If that's what you got from what I said, then your ability to read receives a further challenge.

The Kodak report applies only to the scanners used for checked bags. As I said, the conclusion I draw from it is to carry film through the security line and never put it in checked bags. I thought this was settled knowledge in any case.

The question is why you refute a discussion about the scanners in the security line with a report about the (very different) scanners used for checked bags?

Rick "who never puts film in checked baggage--ever" Denney

Honestly, Rick, I think you need to re-read what the Kodak report says. It is written poorly I agree, but I believe you are misunderstanding it. Also read the report that Brian Shaw posted.

Specifically this...

"Based on the testing completed at the TSA Training Center in Atlantic City, I3A recommends a limit of five passes through the carry-on baggage security checkpoint systems for all color negative and reversal film, including single-use cameras, up to and including ISO 800 speed film. "

[John NYC]

It's really very simple. X-ray exposure, like any exposure, is cumulative. At some number of trips through a scanner a threshold will be crossed and density will be registered in the film. There may be other factors at play influencing exposure, such as the orientation of the film WRT the source, objects in the path that are capable of attenuating X-radiation, etc. Any other prior exposure counts too.

This is exactly right. But don't confuse everyone here with actual science. :-)

[IanG]

This is exactly right. But don't confuse everyone here with actual science. :-)

It's too simple. The carry on luggage scanners are so safe even fertile women are are allowed to use them, no special screens. They don't even need dosemeters, taht just about says it all.

Film safe machines emit no X-ray or other emissions that will harm a film or human, it's that simple.

Ian

[rdenney]

Honestly, Rick, I think you need to re-read what the Kodak report says. It is written poorly I agree, but I believe you are misunderstanding it. Also read the report that Brian Shaw posted.

Well, you're right. "Bettersense" had refuted the notion of cumulative exposure, and that recommendation in the Kodak report certainly does imply that cumulative exposure is possible. My apologies.

And you are right that it is poorly written. There is nothing in that article that provides a basis for that recommendation, given that the equipment they said they evaluated was for checked baggage, and not what is used for carry-on baggage. And before the recommendation you were referring to, they say "X-ray equipment used to inspect carry-on baggage uses a very low level of x-radiation that will not cause noticeable damage to most films."

But you did compare your symptoms to what was in that report, even though their symptoms were caused by the very different equipment used for checked baggage. I was taking things too much in context.

That does not, however, mean that the scenario you noted caused your problem. That said, I have observed truly horrid and often ludicrous behavior by TSA screeners. The notion of a machine operator running it back and forth through the machines just for the purpose of staving off boredom would not surprise me.

Rick "who goes through those security lines just about every week" Denney

[rdenney]

It's too simple. The carry on luggage scanners are so safe even fertile women are are allowed to use them, no special screens. They don't even need dosemeters, taht just about says it all.

I haven't noticed many pregnant women being asked to hop up on the belt and take a ride through the carry-on baggage scanner. The exposure outside the machine and the exposure inside the machine cannot possibly be the same.

Rick "who has never had a problem except with transparency film rated at ISO1000" Denney