The other 2 things I would consider: 1. Capacitance of the body (150pF typically) can be much higher in the situation Ken described, i.e. proximity of the concrete slab with the grid presumably grounded + larger body area close to the floor creating the capacitance. I thing lying on the floor represents the worst case. 2. Harmonic content in AC supply. We always assume 50/60Hz but what if your neighbor runs a welding shop? Besides lower impedance, AFAIK human body is more sensitive to passing current at higher frequency.
I repaired some live 220VAC circuits on occasion and sometimes felt the tool "humming" in my hand but that's all. A friend of mine, an electrician, always said that nothing is wrong as long as you wear rubber sole shoes and keep your other hand in the pocket. Best regards, Alex Gourari From: John Woodgate [mailto:j...@jmwa.demon.co.uk] Sent: Friday, December 03, 2004 3:23 AM To: emc-p...@ieee.org Subject: Re: Is one-handed electrical shock possible? In article <bdd51b4b.1a3af%ken.ja...@emccompliance.com>, Ken Javor <ken.ja...@emccompliance.com> writes >My comment is 22 nF is an awful lot of stray capacitance. If I were in >my screen room and wearing thin soled shoes standing on grounded metal >sheet I could see it, but not in a home environment where there is a >large separation between every part of my body and ground. I think that the answer is 'humidity', not capacitance. The microclimate very close to the surface of a human body can be very humid. This would be especially true a very short time after the initial shock. What we need is a volunteer to hold the live terminal of a phase meter, so we can determine whether the current is resistive or capacitive. And, no, I DON'T MEAN IT! -- Regards, John Woodgate, OOO - Own Opinions Only. The good news is that nothing is compulsory. The bad news is that everything is prohibited. http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/listserv/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Scott Douglas emcp...@ptcnh.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to emc-p...@ieee.org Instructions: http://listserv.ieee.org/listserv/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Ron Pickard: emc-p...@hypercom.com Scott Douglas emcp...@ptcnh.net For policy questions, send mail to: Richard Nute: ri...@ieee.org Jim Bacher: j.bac...@ieee.org All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
