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Author Topic: What type of headwear, and material could protect the head from an ultrasound?  (Read 2838 times)

Offline mriver8

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assault at a freq capable of destroying hair cells? The best I've tried is Grainger closed cell polyurethane foam but it only protects against a numbing tuning fork sensation, and not concentrated/focused zaps.

https://dl-web.dropbox.com/get/127436857-Acoustic-Weapons-A-Prospective-Assessment-Jurgen-Altmann-1.pdf?_subject_uid=317902351&w=AABRd95PNFTrgeib-gQ1M95B9qc9u_wsJkZwk0m_xqaDxg
« Last Edit: 29/09/2014 06:47:23 by mriver8 »


 

Offline chiralSPO

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Just surround your head with a total vacuum. ;) No sound will penetrate.
 

Offline alancalverd

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Ultrasound is reflected at interfaces of materials with widely differing speed of sound. Sound travels through steel at 2 to 3 times the speed in water or soft brain tissue, so the traditional nutter's helmet (a salad colander) on top of a wooly hat will provide adequate protection with good ventilation, but for total security you could wear several layers, say an aviator's leather helmet under a motorbike lid, topped off with a naval anti-flash balaclava and a coal scuttle/Ned Kelly armour.   
 

Offline Bill S

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I tried following the above link and got a message saying I didn't belong there.  Imagine my relief!!
 

Offline jeffreyH

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Ultrasound is reflected at interfaces of materials with widely differing speed of sound. Sound travels through steel at 2 to 3 times the speed in water or soft brain tissue, so the traditional nutter's helmet (a salad colander) on top of a wooly hat will provide adequate protection with good ventilation, but for total security you could wear several layers, say an aviator's leather helmet under a motorbike lid, topped off with a naval anti-flash balaclava and a coal scuttle/Ned Kelly armour.

Now I'm tired and in hysterics.
 

Offline mriver8

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Ultrasound is reflected at interfaces of materials with widely differing speed of sound. Sound travels through steel at 2 to 3 times the speed in water or soft brain tissue, so the traditional nutter's helmet (a salad colander) on top of a wooly hat will provide adequate protection with good ventilation, but for total security you could wear several layers, say an aviator's leather helmet under a motorbike lid, topped off with a naval anti-flash balaclava and a coal scuttle/Ned Kelly armour.

Now I'm tired and in hysterics.
 

Offline mriver8

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I tried following the above link and got a message saying I didn't belong there.  Imagine my relief!!


See attachment. At these frequencies.
 

Offline chiralSPO

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From the second image you posted, it is clear that this is not ultrasound being discussed, but very loud blasts, similar to concussions from bombs or shells. The first image is about high frequencies though...
« Last Edit: 29/09/2014 23:29:05 by chiralSPO »
 

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