1st time operation of Circuit Breaker.

Cat Fan

Member
Location
Phoenix, Az, USA
Table 130.5(C) Estimate of the Likelihood of Occurrence table states, "Operation of a CB or switch the first time after installation or completion of maintenance in the equipment. likelihood yes. Since they added that in 2021 I have seen many different interpretations in the field. Some companies follow it diligently with electricians donning a 40 cal. suite for energizing 20 amp, 120V circuits, low incident energy breakers. Other companies for the higher incident energy, don the suit but for the smaller ones, wear leather protectors and make sure they stand off to the side, and finally the group that ignores it all and just does whatever they want. Was it the intent of NFPA70E team to group all breakers into this regardless to incident energy rating? I am currently working in a building where the distribution panels are energizing and compliance with the statement as written would involve approximately 1000 breakers. There is no exposed bussing for these panels, all dead fronts and panel covers are in place. All panels have incident energy labels installed.
 
NFPA 70E doesn't group everything together. It simply says you need to perform a risk analysis on each of your tasks. It also says turning a breaker on for the first time, after wiring has been done, is very risky, due to possible wiring faults, and therefore you should expect the maximum incident energy should a failure occur. This is different from the simple turn off and turn on of a circuit that is known not to have a fault in the wiring.

Some companies apparently do not trust their qualified employees to perform risk assessments and instead require maximum PPE regardless of what is available.
 
I agree. After first time energization operation of a CB is considered No in likelihood of occurrence. GC's with little understanding of risk assessment are looking at this black and white. I am trying to figure out how to present this in a way that allows for 1st time operation of branch circuits with minimal incident energy to be operated the same way I have been doing it for 30 years, leather protectors, stand to the side. This is a data center cal. rating at the SES is 120 and above, no PPE exist. At the subpanels it drops to 20 and lower. I need to be able to communicate the difference, but they get stuck on the black.
 
Sounds like someone has not been having regular NFPA 70E update training. Risk assessment has been required for more thann10 years now.
 
The question is not about risk assessment it is about how to communicate this to 25 year old superintendents on their first job that are only able to look at the surface of the NFPA70E. I am just going to delete this question as it is easier to give crap than it is advice. thanks for nothing
 
The question is not about risk assessment it is about how to communicate this to 25 year old superintendents on their first job that are only able to look at the surface of the NFPA70E. I am just going to delete this question as it is easier to give crap than it is advice. thanks for nothing
They need to learn that NFPA70E is specifically written in shades of grey. About the only thing in black and white is the use of appropriate PPE. Selecting PPE is about risk assessment. The arc flash incident energy label tells what the worst case condition is if a fault should happen to occur. A risk assessment tells if a fault is likely to occur.

One of the ways to assess the risk is to use the tables in NFPA70E that show reclosing a breaker, that was working when it was opened, is not likely to require arc flash PPE.
Another way to assess risk is to follow the company's electrical safe work practices which say to wear predetermined PPE based on specific tasks.
 
The question is not about risk assessment it is about how to communicate this to 25 year old superintendents on their first job that are only able to look at the surface of the NFPA70E.
Another way to assess risk is to follow the company's electrical safe work practices which say to wear predetermined PPE based on specific tasks.
Communicate to him that you follow company safe work practices or look for another job.

-Hal
 
energizing 20 amp, 120V circuits

I do that wearing a wife beater, shorts, and flip flops LMAO.

Ok, not really, but only because I never dress like that.

25 year old superintendents

You can't win with those kind of college boy morons. They know it all even though they never did it, or even watched anyone do it. And believe me, if you trust one of them they will overlook something important and get someone killed. I've seen them worried about some irrelevant piece of PPE while another moron lifts a 500 pound piece of equipment over other people's heads with rigging made of proof coil chain and nuts, bolts, and piles of washers.

I'm glad I'm old, semi retired and don't have to even see one of those types. None of them are really concerned about safety, they were all taught "See something, say something" from the time they were in preschool. Safety means nothing to them, being a little sissy tattletale like a grade school girl is their goal
 
It seems the line between college boys and "long time" tradesmen gets blurry- especially when one doesnt know how to communicate.
Thanks for nothing? Such a strange thing to say....
 
college boys
I'm not saying there aren't decent guys with stem degrees.

But there are a lot more who are math challenged and are lucky if they read on an 8th grade level who get degrees that get them into management and "supervisory" positions that are more worthless than tits on a bull
 
Table 130.5(C) Estimate of the Likelihood of Occurrence table states, "Operation of a CB or switch the first time after installation or completion of maintenance in the equipment. likelihood yes. Since they added that in 2021 I have seen many different interpretations in the field. Some companies follow it diligently with electricians donning a 40 cal. suite for energizing 20 amp, 120V circuits, low incident energy breakers. Other companies for the higher incident energy, don the suit but for the smaller ones, wear leather protectors and make sure they stand off to the side, and finally the group that ignores it all and just does whatever they want. Was it the intent of NFPA70E team to group all breakers into this regardless to incident energy rating? I am currently working in a building where the distribution panels are energizing and compliance with the statement as written would involve approximately 1000 breakers. There is no exposed bussing for these panels, all dead fronts and panel covers are in place. All panels have incident energy labels installed.
You need an assessment. The campus I work on has the same policy but if you go thru the tables carefully (they have a consultant who does a bi-annual assessment) you find its only really for the 480V and over panels you need more than gloves.
240 and 208 panels are exempt according to our safety assessment.
 
Here's my two cents after 50 years as a sparky.. Would feel ten times safer turning on a 20 amp 120 volt circuit breaker only wearing 10 CAL PPE including an approved tinted face shield using common sense method of standing to one side of breaker, using your left hand ( if right handed as told by an old timer saying you still will be able to wipe yourself if their is an Arc fault ) and taking in a deep breath & holding it until power is turned on. ( In a serious Arc blast you could inhale super heated air causing serious lung burns. That to me is safer then a person in 40 CAL ( which we only needed for 4,160 & 13,200 volt switchgear ) standing directly in front of a circuit breaker they are turning in and breathing normally. I never saw or heard of a 120 volt circuit breaker blowing apart and injuring anybody. Back in the 1970's we had a few pushmatic panels flush in boning rooms at a meat packer. We siliconed top of panel to packing house walls but with nightly wash downs water would enter and we would unscrew the top water damaged single pole breaker and have to chisel the rusted steel side of breaker off while panel was hot. Back then we only wore safety glasses while doing that work. Could not pay me enough to do that now a days.
 
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