Re: RF biological hazards? (fwd)

---------- Forwarded message ----------
Date: Wed, 6 May 1998 09:15:22 +1200
From: Malcolm Watts <MALCOLM-at-directorate.wnp.ac.nz>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re: RF biological hazards? (fwd)

Hi Jeff,
          The answer lies in the mode of operation.....

> Date: Mon, 4 May 1998 18:19:44 -0500
> From: Jeff Corr <corr-at-enid-dot-com>
> To: Tesla List <tesla-at-pupman-dot-com>
> Subject: Re: RF biological hazards? (fwd)
> There are serious debates here, and we all know of the supposed
> "Skin Effect."  It is very observable on small scopes.  A 9kv, 30ma
> powering my 2"x10" coil, with 10" sparks can not be felt at all, but
> my 6"x26", well, I won't touch it again.  Where is the dividing line?
> They are both high voltage, low current, high frequency coils...
> Why is the small one unnoticable, while the large one causes unimaginable
> pain?  I suppose go by the saying : "If it hurts, don't touch it?"

     RF output is not continuous. It is a series of damped rings 
occurring at a frequency well below where the skin effect would come 
into play i.e. the repetition rate is << than the resonant frequency. 
This particular hazard doesn't exist with a CW run coil but that 
doesn't preclude penetrating burns in nervous tissue etc.

    IMO the best way to ascertain whether a shock hazard exists is to 
look at primary energy (Joules). The other thing is that if you 
connect with streamers at the farthest distance you can, some
rectification appears to be occurring and you can get very
substantial shocks, even with a very low primary energy.