Electricity Safety: AC & DC Current Limits for Intro Physics Labs

AI Thread Summary
The discussion centers on safe limits for AC and DC currents in introductory physics labs, highlighting concerns about the dangers of DC currents, particularly the risk of being unable to let go of a live wire. A referenced chart outlines current limits for various body effects, prompting questions about its validity. Participants emphasize the importance of adhering to safety guidelines, suggesting that staying below 50V is prudent, as higher voltages require specialized training. The conversation stresses that while both AC and DC currents can be hazardous, the focus should be on the current itself, as it is the primary factor in electrical injuries. Participants caution against underestimating the dangers of electricity and recommend consulting qualified experts for safety advice rather than relying on informal online discussions.
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I would like to ask the experienced experts about the safe limits for AC and DC currents to be used in intro physics labs. People say DC is dangerous because one can’t let go of the wire if the wire was carrying certain DC current.

Following link has a chart with current limits for AC and DC for various body effects. Do you agree with this chart?

http://www.allaboutcircuits.com/vol_1/chpt_3/4.html

Thank you!
 
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I think that kind of advice is against the forum rules since if we give advice and you follow it and someone gets hurt you could sue and then Greg could have a problem. Sounds farfetched, perhaps, but it out litigious society you can't be too careful.
 
Stay below 50V - in the US over that you need to be a Qualified Individual - basically meaning you have been trained sufficiently to be aware of the hazards in your work environment and understand how to avoid them.

AC / DC does not matter - do not get hung up in that. Voltage and Current do not get hung up on that ether!

The point in the post is that technically current is what does the damage - but it is like saying speed does not kill - it is the rapid deceleration. PLEASE do not confuse or compare human physiology with personal safety - ELECTRICITY can and will kill you.
 
See phinds, we won't discuss this here. Ask an expert (not in internet forums) before you use anything that could be dangerous.
Windadct said:
AC / DC does not matter - do not get hung up in that. Voltage and Current do not get hung up on that ether!
It can matter, as a human has some capacitance against the environment and you get different effects in tissue if the current directions gets reversed frequently.

PLEASE do not confuse or compare human physiology with personal safety - ELECTRICITY can and will kill you.
Let's hope it won't...
 
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