Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!cs.utexas.edu!usc!wuarchive!mit-eddie!uw-beaver!uw-entropy!dataio!pilchuck!seahcx!phred!jeffp
From: jeffp@phred.UUCP (Jeff Parke)
Newsgroups: sci.electronics
Subject: Re: power from phone line
Message-ID: <2883@phred.UUCP>
Date: 8 Dec 89 17:51:21 GMT
References: <14230@jumbo.dec.com> <3542@kitty.UUCP> <6300@lindy.Stanford.EDU> <5651@internal.Apple.COM>
Reply-To: jeffp@phred.UUCP (Jeff Parke)
Organization: <5651@internal.Apple.COM>o
Lines: 20

In article <5651@internal.Apple.COM> ems@Apple.COM (Mike Smith) writes:
>...
>Most lethal is a LOW current modest voltage signal that ocilates at
>a particularly sensitive frequency to the heart muscle.  I've forgotten
>the frequency and if it was AC or pulsed DC. 

It turns out that the most lethal frequencies for putting out your heart are
in the 40-100 Hz range.  60 Hz isn't a good one.  Most deadly would be a
small (threshold) current, since larger currents can actually get the heart
going again - all depending on duration of contact and factors about the
subject heart's own susceptibility.

Early defibrillators (devices that deliver large current/voltage to start up a
fibrillating heart) actually used 60 Hz, but were not especially effective.

Modern, effective defibrillators are all DC; they deliver a 5 to 15 ms long
single monophasic or biphasic waveform.
-- 
...dataio!pilchuck!phred!jeffp {Jeff Parke}
Genie  : JEFFP  | DELPHI : JEFFPARKE |  CIS : 71511,1512