[comp.sys.mac.hardware] Floppy Disks and X-Rays

feldman@vax.oxford.ac.uk (06/07/91)

How sensitive, if at all, are 3.5" floppy disks to airport-type
security x-rays?  I have to bring about 100 disks on the plane,
and the disks contain my only copies of all the software on them.

Is there any worry?  Are there any precautions to take?

Thanks very much - please post or e-mail answers.

Todd

sie6@quads.uchicago.edu (scott alexander siege) (06/08/91)

How are disks affected by X-rays? X-rays will not hurt disk. BUT READ ON!!!!!

The problem with those airport X-ray machines is in the conveyor belts etc.
Large motors run the conveyor belts. These motors and all sorts of other 
things associated with machinery create large magnetic and electrical fields.
These fields "can" hurt disks.  (I put can in quotes because I am sure many
many people will write back sayong they have never had any trouble with disks.
But, it is possible and you know what Murphy would say...)  
The bottom line is: Have bags containing disks hand searched. And, never travel
AT ALL with the only copy of ANY data.

-Scott

peted@com.microsoft (06/11/91)

In article <1991Jun6.190601.616@vax.oxford.ac.uk> you write:
>How sensitive, if at all, are 3.5" floppy disks to airport-type
>security x-rays?  I have to bring about 100 disks on the plane,
>and the disks contain my only copies of all the software on them.
>
>Is there any worry?  Are there any precautions to take?
>
>Thanks very much - please post or e-mail answers.
>
>Todd

All of the information I've seen about this say that the x-rays
themselves aren't harmful to the disks.  But, you still need to
be careful because the electromagnets in the x-ray machines monitors
and emitters _can_ erase data.  The chance isn't great, but it is
non-negligable.  The best thing would be to just have the disks
hand checked.


-- 
Pete Duniho                "There are two kinds of men in this world:
Excel Development             those with loaded guns, and those who dig."
---
Pete Duniho                "There are two kinds of men in this world:
Excel Development             those with loaded guns, and those who dig."

tap@iti.org (Thomas A. Phelps) (06/11/91)

Please note that the magnetic fields which emanate from airport x-ray
machines are not contained within the machine.  I had a floppy corrupted
when I handed it past the machine to the security person.  Be very wary
of such equipment.  If you need the data on the other end, check a copy
through in your checked luggage (I know, I don't like to check luggage
either).  Of course, checked luggage can also be zapped.  Best bet is to
use another shipping method altogether, at least for one copy.  Instead
of dragging 100 disks along on the airplane, send a duplicate set via UPS
or other common carrier.  

Disks are cheap via mail order, nowadays.  Check out MEI/Micro Center
800-634-3478.  They have terrific prices.  Last I saw, 1.44 Meg floppies
were $.59 each in lots of 25.  Duplicates are cheap insurance.

MacUserLabs@cup.portal.com (Stephan - Somogyi) (06/13/91)

feldman@vax.oxford.ac.ukw asks:
 
>How sensitive, if at all, are 3.5" floppy disks to airport-type
>security x-rays?  I have to bring about 100 disks on the plane, and
>the disks contain my only copies of all the software on them.
 
>Is there any worry?  Are there any precautions to take?
 
As someone else already mentioned, the x-rays themselves aren't the
problem (any more), the magnetic fields generated by the conveyor belt
motors are.
 
I've been travelling internationally with hard disks in my carry-on
luggage for a few years now and haven't lost data on either HDs or
floppies. As a caveat to this I must qualify that all of the airports
that I have gone through appear to have up-to-date equipment. It's
quite plausible that older equipment will eat data.
 
Most airports will allow electronic equipment or magnetic media to be
hand checked, even if it takes a little orneriness on your part to
make them do it. I don't even bother any more.
 
Heathrow, however, will NOT. I flew through there last year just after
they had instituted this rule and was told in no uncertain terms that
I could either put my HD through the machine or not get on my plane.
As of Sunday, this rule is still in effect.
 
______________________________________________________________________
Stephan Somogyi                   net.nerd                     MacUser

kik@isr.harvard.edu (Ken Kreshtool) (06/13/91)

In article <tap.676657527@hela.iti.org> tap@iti.org (Thomas A. Phelps) writes:
>Please note that the magnetic fields which emanate from airport x-ray
>machines are not contained within the machine.  I had a floppy corrupted
>when I handed it past the machine to the security person.  Be very wary
>of such equipment.  If you need the data on the other end, check a copy
>through in your checked luggage (I know, I don't like to check luggage
>either).  Of course, checked luggage can also be zapped.  Best bet is to
>use another shipping method altogether, at least for one copy.  Instead
>of dragging 100 disks along on the airplane, send a duplicate set via UPS
>or other common carrier.  

Was it the x-rays?  Was it the metal-detector?  (Good advice about the dupes.)

Ken Kreshtool
kik@wjh12.harvard.edu

topix@gpu.utcs.utoronto.ca (R. Munroe) (06/13/91)

In article <1991Jun13.005554.6874@burrhus.harvard.edu> kik@isr.harvard.edu (Ken Kreshtool) writes:
>In article <tap.676657527@hela.iti.org> tap@iti.org (Thomas A. Phelps) writes:
>>Please note that the magnetic fields which emanate from airport x-ray
>>machines are not contained within the machine.  I had a floppy corrupted
>>when I handed it past the machine to the security person.  Be very wary
>> ......
>
>Was it the x-rays?  Was it the metal-detector?  (Good advice about the dupes.)
>
>Ken Kreshtool
>kik@wjh12.harvard.edu


From what I understand, X-rays themselves do not zap the data on floppies
(or other magnetic media).  What does zap the data are the magnetic fields
emanating from the electronic components that run the x-ray machine.
These fields are not present on all machines, but there is no way to
find out in advance - so caveat travellor.

Bob Munroe
topix@utcs.utoronto.ca

JXY2@psuvm.psu.edu (Jie Yuan) (06/13/91)

In article <tap.676657527@hela.iti.org>, tap@iti.org (Thomas A. Phelps) says:
>
>Disks are cheap via mail order, nowadays.  Check out MEI/Micro Center
>800-634-3478.  They have terrific prices.  Last I saw, 1.44 Meg floppies
>were $.59 each in lots of 25.  Duplicates are cheap insurance.

I was interested in 3.5 in HD floppies and called them.  It was $.59/ea
in lots of 25 with $.50 for shipping per lot (of 25) and handling of $3.00
per order.  The total would be $18.24 if you order a lot of 25, averaging
$.73/ea.  It would be cheaper if you order more since the handling fee
is fixed per order.


Jie Yuan
jxy2@psuvm.bitnet
(814)863-4266 (Lab)
     237-8528 (Home)