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July 1997

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From:
[log in to unmask] (Doug McKean)
Date:
Fri, 25 Jul 1997 10:24:58 -0400
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Yes, if it was my decision to make, I would.  

An electrical ground is simply the building ground with 
very little resistance.  In other words, if one were to 
measure electrical  ground between two points anywhere 
in your building, the measurement would/should be in the 
ohms or 1/10 of ohms - very low.  

When any amount of charge is discharged to electrical 
ground, the discharge current is high and damaging. 
There is no resistance to limit the current.  Charge that 
has built up on some assembly, even a small amount, 
would damage the assembly being discharged. 

On another note, it's also essentially  unsafe.  If there was 
ever the possibility that someone grabbed something 
hot with 120 vac line voltage and were grounded to 
electrical ground with simply some wire, the result 
would be ...  well, take it from there.  

ESD ground on the other hand has a high resistance 
to it up in the Meg ohms.  This allows safe discharge 
currents from electronic assemblies.  It is also safe 
with someone grabbing AC by accident in the sense 
that it should allow one to release their grip on the 
live wire.  I believe the upper limit for voluntary release, 
the maximum current where you can let go of something 
hot, is roughly 5 milli-amps through your muscle and 
is dependent upon many factors.  Above this point, 
you can't release your grip.  I could be off on this one 
but I think I've made my point - 

	People safety first, 
	then product safety second.  

Never reverse it. 

Flooring can be made into ESD ground in a number 
of different ways depending upon the necessity - 
from leaving the floor as bare concrete, to conductive 
paint, to conductive tiles.  You'll need to contact 
a consultant preferably someone not selling a 
specific product, or read up on this topic. 

I would recommend that you thoroughly research 
the subject of ESD before you make any decisions 
for your specific situation.  

And please, keep it safe. 

Regards ... 

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