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 Post subject: 2018 70E
PostPosted: Tue Aug 01, 2017 12:30 pm 

Joined: Tue Feb 17, 2009 11:04 am
Posts: 37
Will there be 8 steps to establish an Electrically Safe Work Condition? If so, what are the 2 new steps? Thanks in advance for your response.


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 Post subject: Re: 2018 70E
PostPosted: Tue Aug 01, 2017 2:27 pm 
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Location: Scottsdale, Arizona
Yes, verification of an electrically safe work condition was relocated from 120.1 to 120.5 and two new steps were added:

(4) Release stored electrical energy
(5) Release or block stored mechanical energy

They are inserted at position 4 and 5 in the list of steps for a total of 8.

2018 NFPA 70E Changes Article


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 Post subject: Re: 2018 70E
PostPosted: Wed Aug 02, 2017 11:55 am 
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Jim Phillips (brainfiller) wrote:
Yes, verification of an electrically safe work condition was relocated from 120.1 to 120.5 and two new steps were added:

(4) Release stored electrical energy
(5) Release or block stored mechanical energy

They are inserted at position 4 and 5 in the list of steps for a total of 8.

2018 NFPA 70E Changes Article


Interesting. No matter how many times I look at it, "grounding" is one of those things that nobody can seem to agree on. Prior to this version draining capacitive charge (discharge stored electrical energy) was all but absent from any standard or regulation. It generally gets tied up with two other steps...applying grounding and testing for absence of voltage.

There are definitely 3 different issues to be addessed...discharging stored charges, shorting things out to avoid actual existing voltages that cannot be eliminated (e.g. two overhead lines on the same pole structure with different circuits), and testing to make sure that there is no residual voltage. There are different orders to these steps in both 70E and NESC but get it wrong and the result can be physically very hazardous.


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