Naked Science Forum

Non Life Sciences => Physics, Astronomy & Cosmology => Topic started by: Mr Andrew on 28/09/2007 00:36:55

Title: Metal Detectors
Post by: Mr Andrew on 28/09/2007 00:36:55
I know a guy who broke his leg so bad that he had to have a steel rod put in his leg to strengthen the bone.  Is there some way to make this rod unable to be detected in a metal detector?  I know they work because of induction and I also know that a disk with slots in it doesn't carry an induced current very well.  Is there some way to combine these ideas and still end up with a strong steel reinforcement for this guy's leg?
Title: Metal Detectors
Post by: JimBob on 28/09/2007 01:37:10
Not yet. I have artificial hips and a lot of metal. I set off the airport detector and I have He** getting to a gate. I need a full body search - rather embarrassing - a complete X-ray or fluoroscope even though I have a card issued by my local airport and signed by my orthopedic surgeon that I have them. It just doesn't have my picture on it so I get the full treatment anyway.

I don't travel by air often.

Title: Metal Detectors
Post by: another_someone on 28/09/2007 01:44:55
Metal detectors will detect most metal objects, and I don't think that putting slots will have much influence (it depends on the frequency on the induced signal, and the spacing of the slots; but in general metal detectors are intended to pick up very small metal objects, even keys - so the slots would have to be spaced closer than the size of a key to have any impact).

The only way of not being detectable by a metal detector really is not to use metal.  Other materials can easily be as strong, but the problem is finding something that is sufficiently biologically inert so as not to cause blood clots, or other adverse biological reaction.

I suppose one could look towards the kind of stealth technology used to avoid detection by RADAR (RADAR is just a fancy form of metal detector).
Title: Metal Detectors
Post by: Karen W. on 28/09/2007 04:34:56
Not yet. I have artificial hips and a lot of metal. I set off the airport detector and I have He** getting to a gate. I need a full body search - rather embarrassing - a complete X-ray or fluoroscope even though I have a card issued by my local airport and signed by my orthopedic surgeon that I have them. It just doesn't have my picture on it so I get the full treatment anyway.

I don't travel by air often.



Jim bob what about petitioning the government to allow some sort of picture id for you which would include all of your wonderful hardware! Wouldn't it be pretty simple to have that on one simple card for folks who have implants or perhaps a prosthesis?
I have a leg in my closet.. but I believe it has a titanium shin that goes into the attached shoe! I am pretty certain titanium would also do it!

JimBob when they replaced your hips was that done with metal also or is the joint some kind of heavy duty Plastic or something. It seems that plastic could eventually cause a problem breaking down in the body! Toxins etc. Would it??