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Regarding testing at the point of work what have you done?
We’ve always tested absence of voltage at the point of work 74%  74%  [ 17 ]
Not always but will begin doing that now 13%  13%  [ 3 ]
Not applicable 13%  13%  [ 3 ]
Something else (explain) 0%  0%  [ 0 ]
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 Post subject: Testing Absence of Voltage at POINT OF WORK
PostPosted: Sun Aug 27, 2023 5:19 pm 
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Location: Scottsdale, Arizona
The text “at each point of work” was added to step 7 of the Process for Establishing and Verifying an Electrically Safe Work Condition.

Step 7 is testing absence of voltage and the language now states:
Use an adequately rated portable test instrument to test each phase conductor or circuit part at each point of work to test for the absence of voltage.

Here is a short video where I explain the new addition: Short Video - At each point of work

Regarding testing at the point of work what have you done?
We’ve always tested absence of voltage at the point of work
Not always but will begin doing that now
Not applicable
Something else (explain)

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 Post subject: Re: Testing Absence of Voltage at POINT OF WORK
PostPosted: Mon Aug 28, 2023 10:37 am 

Joined: Fri Sep 28, 2018 7:32 am
Posts: 30
Location: Sioux Falls, SD
Jim, the clarification makes perfect sense. I have two scenarios to clarify.
1) I de-energize an MCC by opening and upstream switch. May I test for absence of voltage once at the incoming MCC terminals or shall I test within every compartment where work is being performed?

2) I am having a facility wide outage, let's say to perform de-energized preventative maintenance. The utility de-energizes the service. Personnel must confirm the absence of voltage at every equipment being accessed?

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 Post subject: Re: Testing Absence of Voltage at POINT OF WORK
PostPosted: Tue Aug 29, 2023 7:33 am 

Joined: Mon Apr 29, 2019 5:24 pm
Posts: 29
Location: Phoenix, AZ USA
I was very pleased to see the addition of the "at each point of work" to 120.6(7) in the 2024 edition of 70E, because it provides additional clarity that was lacking. However, I also believe it should be further enhanced to fill another gap that's far too common and has caused many serious injuries and fatalities. While the update to 120.6(7) is a good start and will most certainly help accidents where the work scope is narrow, such as working on a motor, distribution panelboard, and other load equipment with only one source that’s LOTO. However, the gap involves wide jobs such as routine clean and inspection of large equipment such as switchgear and MCCs which has many separate compartments being fed by multiple different sources, such as those with hard cross ties, main-tie-main, etc. Depending on the worksite, sometimes it is not possible to deenergize all the feeders entering the gear, because they are powering other critical loads. This means, specific portions of the gear is placed into an ESWC to be cleaned and inspected, while other compartments remain energized. This means to fully perform the maintenance task, the job must be separated into two or more steps, with the LOTO isolation point(s) moved from one device to another. It’s common to use flagging devices, such as red barricade DANGER tape to establish a “tape in and tape out” to identify which compartments or enclosures are prohibited from access because they contain energized parts.

While this is an excellent HU practice, which is listed in Annex Q, Table Q.5, it isn’t perfect because it relies on human beings to tape off the correct compartments, and because the job is fluid and dynamic, the worker must move the flagging method for every evolution of the job to identify different compartments that now house deadly energized parts that a couple of hours ago, were in an ESWC. The task of moving from compartment to compartment, is a significant error precursor, and when coupled with precursors like complacency, overconfidence, time pressure, high workload, distractions, interruptions, unfamiliar with the task, etc. then the holes in the Swiss cheese start lining up. The solution would be a requirement to reperform the absence of voltage (Live-Dead-Live) as the worker moves from compartment to compartment or enclosure to enclosure.

On October 20, 2021 we nearly lost an electrician during a routine clean and inspect of a 13.8kV switchgear, that had three sources feeding the bus. Two of the three sources were placed and verified to be in an ESWC, while the third needed to remain energized. The electrician properly flagged of the front and back doors of the energized cubicle, but due to unfamiliarity with this style of gear, he failed to also flag off an adjacent cubicle that housed two sets of potential transformers (PTs). One of the PT sets was still energized due to conductors routed through the wall between the energized compartment and the adjacent compartment with the PTs. As he proceeded in his job and moved from one compartment to another, he accessed the one with the energized PTs conductors and nearly lost his life. In speaking with the injured worker after the accident, he told me “I thought about doing another Live-Dead-Live before touching the part but I had already done one just a few minutes earlier in another compartment.”

But this incident isn’t an outlier or a one-time occurrence. During my research I was able to identify several other similar incidents during “routine clean and inspection”. One of the incidents occurred on May 3, 2015 at the Los Alamos Testing Laboratory in New Mexico. Interestingly the details of this accident were presented during the 2020 ESW in Reno, NV by Tommy Martinez and Julian Trujillo, paper # ESW2020-31.

During this year’s 2023 ESW in Reno, I presented a paper titled “Is Absence of Voltage ‘Live-Dead-Live’ Testing According to NFPA 70E Adequate?”, paper # ESW2023-32, that carefully examined this far too common deadly oversight and offered a solution to update 70E by including additional instructions to re-perform the absence of voltage (LDL) with sometime like “If moving from the original defined work area, for example: moving from one compartment, enclosure or part of the same equipment to a different area that has not been previously LDL tested, then a LDL check shall be performed to test each and every exposed part(s) with the new location.”

Hopefully this or something similar with be accepted during the 2027 edition of 70E.

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 Post subject: Re: Testing Absence of Voltage at POINT OF WORK
PostPosted: Tue Aug 29, 2023 7:41 am 

Joined: Mon Apr 29, 2019 5:24 pm
Posts: 29
Location: Phoenix, AZ USA

Please read my post as it will probably answer your questions.

Even if 70E or OSHA regulations don't specifically call out a mandatory safety practice, if you know there are proven good practices based on the learning of others who found out the hard way, then I'd say we should learn from one another. This one reason Jim started the forum, so we could share and learn from each other.

Our number one priority is to keep our workers safe, so they go home in the same condition they arrived in.

Take care and stay safe Mr. Moore.

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