OPERATE BREAKERS AFTER A STUDY

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hawkeye23

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If there has been a study on electrical equipment and labels are posted on each panel does a worker have to be suited up with the level of ppe stated on the labels to open or close cb ? We have people who feel they can open or close a cb without ppe because of one thing - doors are closed and feel labels are only when the doors are open.
Can someone point to a 70e code that states this rule ?
 
hawkeye23 said:
If there has been a study on electrical equipment and labels are posted on each panel does a worker have to be suited up with the level of ppe stated on the labels to open or close cb ? We have people who feel they can open or close a cb without ppe because of one thing - doors are closed and feel labels are only when the doors are open.
Can someone point to a 70e code that states this rule ?
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You will not find that in 70E for the simple reason that it does not recognize doors or enclosures as reducing the Arc Flash hazard level. The enclosures are not tested for that.

Some have questioned the applicability of PPE requirements when using 20A breakers in a load center for controlling lighting, but for larger CBs, there does not seem to be much argument among those educated on the subject.

Also, as described in another thread, the arc flash energy can easily extend through a multi-bucket installation to reach a vent.
 
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It depends upon who makes out your paycheck. If your job description requires you to follow safety procedures to suit up wit ppe then it's a none issue. Even though it may not be part of the company's safety standards who is liable should there be an incident? I would clarify this with those that sign you paycheck.
Don't ask others, ask your employer what they expect.
 
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Temp, I don't think asking my employer is not going to give me the right answer for what maybe right for us employees.
There are many smart electricians on this forum and if I can find the correct answer or more information to my post by asking it here i'ii take it.
I searched 70e and the only thing I found with regards to my post was in the 2012 70e code 205.3 .
So if there is something I missed and someone has more information to this post it would help me get this across to the powers that be.

Thanks for your time and input.
 
Hawkeye,
NFPA 70E, 90.2 Scope definition, says that the standard is applicable for interacting with electrcial systems. Interact is: install, inspect, operate, maintain and demolish.
If there were no labels on the equipment, you'd use the tables for PPE determination. And the tables support the contention that there is risk associated with the operation: e.g. 130.7(C)(15)(a); Metal Cald switchgear, 1-38kV - CB operation with enclosure doors closed is HRC 2.
But if a Study determined the incident energy levels and labelled accordingly you must use that PPE level for interacting with it, even just operating the breaker.
Your employer could consciously reduce the HRC level by applying the 70E Annex F, Hazard Analysis, Risk Estimation, and Risk Evaluation Procedure to reduce the HRC level from the PPE level developed in the Study, but the fact remains that the doors were never designed to contain an arc flash or blast, so conventional logic says you must treat it as if there's no advantage to the door being closed.
For your own personal safety, recognize the danger associated with a piece of equipment as defined by the AF label. If it's HRC Dangerous, you need a remote operator to turn the switch. Otherwise, use PPE per the labels, per 70E, per OSHA.
 
One of our services is 4000 amp 480V . It's labeled Dangerous , 94 cal/cm 2 . We have molded case breakers on this from 2000 amp to 400 amp . From what I am reading does that mean we should be using PPE when operating any of these breakers ? Also if thats the case would PPE need to be rated above 94 cal/cm 2 ?
 
Davebones said:
One of our services is 4000 amp 480V . It's labeled Dangerous , 94 cal/cm 2 . We have molded case breakers on this from 2000 amp to 400 amp . From what I am reading does that mean we should be using PPE when operating any of these breakers ? Also if thats the case would PPE need to be rated above 94 cal/cm 2 ?
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Yes, problem is PPE will only protect you from the burn, not the pressure, so many feel a Ei >40cal/cm2 is the level where PPE is no longer effective. Most companies use remote operators in this case.
 
hawkeye23 said:
Temp, I don't think asking my employer is not going to give me the right answer for what maybe right for us employees.
There are many smart electricians on this forum and if I can find the correct answer or more information to my post by asking it here i'ii take it.
I searched 70e and the only thing I found with regards to my post was in the 2012 70e code 205.3 .
So if there is something I missed and someone has more information to this post it would help me get this across to the powers that be.

Thanks for your time and input.
Click to expand...
Yes, I agree that there are 'many smart electricians out there' and as such they would be smart enough to realize who signs their paycheck.
I have found it very common for those who search for an answer that they want to hear not it's the correct answer. You appear to have chosen to avoid your employer's position, you know, the one who sign you paycheck and pays the insurance company that insures their employees from on the job injuries. By being a maverick in the eyes of you employer may not be the best thing for you to do.
Should your employer be disinterested in what you are attempting to do at least you have you back side covered.
Who would OSHA come after should it be an incident for the to investigate you or your employer?
 
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Temp , thank you for your help. I will take in all the responses that the people on this forum gave. The thing you do not understand is this is 'to help me, my fellow workers and my company . This is trying to be safe and not being a maverick. Again a big thank you
 
Just going over all the replies to my post and come to believe that some may think I was attempting to not use ppe when operating a breaker in panel [300a ] with doors closed . Well it is just the opporsite , I feel you need to use ppe anytime you interact with a breaker , these panels have arc flash labels on them . I just could not convince my employer of this, could not show any support in 70e to back this claim.
All equipment is in the <600 volt limit.
 
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hawkeye23 said:
Just going over all the replies to my post and come to believe that some may think I was attempting to not use ppe when operating a breaker in panel [300a ] with doors closed . Well it is just the opporsite , I feel you need to use ppe anytime you interact with a breaker , these panels have arc flash labels on them . I just could not convince my employer of this, could not show any support in 70e to back this claim.
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Post # 5 should give you a lot of ammunition. If a breaker with the door closed is considered HRC 2 in the absence of an study, then clearly the door being closed does not constitute much protection.
And if the individual breaker location is HRC Dangerous from a study, just as the service itself is, then there is actually no level of PPE that will allow interacting with those breakers when hot.
Powering off upstream or using remote operating hardware are the remaining alternatives.
 
This is a 480volt level breaker 300-400amp with a level 4 hr/c label and safety department said it was ok to operate when needed to . I took a look at the tables which was recommended here to see if we did not have a study what the risk would be with the doors closed , all I found was a 0 hr/c . also should' nt that person who would open or close the breaker have to be QW as in 70e ?
 
That's clearly a case where level 4 PPE must be worn to operate the breaker.
And yes, the worker should be qualified to perform that task, with training for the specific hazards associated with the task, which would include recognition of the PPE 4 requirement.
You'll need to educate your Safety group before someone gets hurt.
.. and to address your comment about the Tables showing HRC 0:
The tables are very restricitive as to their applicability. Look at the specific case where you found HRC 0 for the task to see if there are any qualifiers, like max fault current, or ocpd clearing time for upstream device, and chances are your specific application is not covered.
But regardless, if arc flash calculations have been performed, and there's a label on the panel, you can't use the tables, and must honor the label.
I only used the tables as a reference in my initial post to show that there are cases where the tables do not show HRC 0 with doors closed. That shows your Safety folks that DOORS CLOSED IS NOT HRC 0.
 
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mayanees said:
... and must honor the label. ....
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If you are using a calculated Incident Energy value, you should make a conscious effort to stop referring to a Hazard Risk Category.
HRC is a term specifically for the task tables, it incorporates some amount of risk assessment.
When you put a calculated Incident Energy value on a label you are simply stating what hazard exists. Your Safe Work Practices program should address the risk issue.

Have you noticed how 70E does not ever tell you what clothing must be worn when you perform calculations?
The 70E tables describe specific clothing for HRC 2 and limit it to 8 cal/cm?, however the 'optional' annex lists the same PPE list as being acceptable up to 12 cal/cm?.

I know that HRC has been used as a generally accepted term for PPE selection and to a degree this sounds a little like an argument over semantics. But, from what I have seen proposed for the next edition of NFPA70E, this distinction will be very important.
 
jim dungar writes: If you are using a calculated Incident Energy value, you should make a conscious effort to stop referring to a Hazard Risk Category.

Point taken.
Thanks
 
hawkeye23 said:
Just going over all the replies to my post and come to believe that some may think I was attempting to not use ppe when operating a breaker in panel [300a ] with doors closed . Well it is just the opporsite , I feel you need to use ppe anytime you interact with a breaker , these panels have arc flash labels on them . I just could not convince my employer of this, could not show any support in 70e to back this claim.
All equipment is in the <600 volt limit.
Click to expand...

That is the main problems sometime as the employers does not give full independence of work, whether they know or not and this could be harmful for them sometime in the future, but we cannot do anything with this except trying to convince them.
 
zog said:
Yes, problem is PPE will only protect you from the burn, not the pressure, so many feel a Ei >40cal/cm2 is the level where PPE is no longer effective. Most companies use remote operators in this case.
Click to expand...

the instructor who gave me my arc flash training said that suits beyond
40 cal aren't going to protect you from the pressure wave, and above
40 cal is in the lethal range for pressure.

the requirement for foam earplugs to prevent broken eardrums at
level 4 reflects the level of energy present.
 
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