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 Post subject: PPE for 120V receptacle?
PostPosted: Thu Jun 04, 2009 8:32 pm 

Joined: Fri Sep 05, 2008 8:10 am
Posts: 36
In NFPA 70E (2009) Table 130.7(C)(9) states "Work on energized electrical conductors and circuit parts of utilization equipment fed directly by a branch circuit of the panelboard" has an HRC of 1.

Does the common interpretation of this mean that work done on a 120V receptacle requires HRC 1 PPE?

The energized work I speak of is for troubleshooting or testing. I don't see a reason to perform non-testing energized electrical work on a 120V receptacle.

As always, thanks.


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PostPosted: Thu Jul 16, 2009 2:09 pm 

Joined: Mon Jun 15, 2009 9:11 am
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Location: Connecticut
Good question except you need to read NFPA70E a little closer. First a 120 volt receptacle is single phase and usually has a 14 awg conductor, 15 amp breaker or 12 awg conductor, 20 amp breaker. This alone would give very, very low short circuit fault potentials. NFPA 70E states any circuit 240 volt or less and supplied by a 125 kva or less transformer is exempt. The premise is there is not enough current capability to maintain an arc flash. Therefore 120 volt receptacles don't qualify to be rated.


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PostPosted: Sat Aug 15, 2009 3:07 pm 

Joined: Wed Oct 29, 2008 6:05 am
Posts: 38
This is my interpretation....

A quick arc-fault calculation will probably reveal that this is fed from a transformer that in less than 125KVA. Since it is less then 125KVA, no arc-fault calculations are required and you can label this as HRC 0.


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PostPosted: Wed Aug 19, 2009 2:58 am 
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Location: Lawrenceburg KY
Gloves?

If you speak of Class 0 gloves PPE shock protection for 120v? There are a few opinions on this that I have found in the past. I cannot find the link but, there is a letter of interruption that comments on using gloves on 120v ac. Say for testing a receptacle outlet with a meter. Example of exception was test leads that would stop the fingers from slipping and touching the probe tip and no other components in the area that can be touched etc.. The key I suppose is the prohibited approach area for shock protection. In this case, do not touch.


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PostPosted: Sun Aug 30, 2009 4:56 pm 
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Joined: Mon May 18, 2009 5:25 pm
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Location: Miami Fl.
MIEngineer wrote:
In NFPA 70E (2009) Table 130.7(C)(9) states "Work on energized electrical conductors and circuit parts of [color="Red"]utilization equipment[/color] fed directly by a branch circuit of the panelboard" has an HRC of 1.

Does the common interpretation of this mean that work done on a 120V receptacle requires HRC 1 PPE?





A receptacle is a contact device and not utilization equipment.

Quote:
Utilization Equipment. Equipment that utilizes electric energy for electronic, electromechanical, chemical, heating, lighting, or similar purposes.


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PostPosted: Mon Aug 31, 2009 3:38 am 
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Location: Lawrenceburg KY
MIEngineer,
This is the link to what I was speaking too earlier it’s not OSHA but is by BNL Electrical Safety Committee interpretation.

I believe the word PANEL is referring to 3phase 240 volts or less and the device is a panel board say for lighting, heating, hvac etc. As mentioned by Chris. I reach this conclusion because, AF hazard is calculated by using 3 Phase short circuit data in the formulas used to determine the hazard level.

My interpretation of this is not of a receptacle but a three phase circuit breaker feeding a device such as a heater or HVAC system. And the person is working with such equipment.

Moreover, the statement by, PAult I agree with. If the exception is met then you must only be concerned with shock hazard.
+
[url="http://www.bnl.gov/esh/esc/PDFs/Use%20of%20Voltage-Rated%20Gloves%20-%20120V%20Single%20Ph.%20Circuits.pdf"]http://www.bnl.gov/esh/esc/PDFs/Use%20of%20Voltage-Rated%20Gloves%20-%20120V%20Single%20Ph.%20Circuits.pdf[/url]


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