ARC FLASH LABELING - NFPA 70E Article 130.5 (D) Equipment Labeling

[PE (always learning)]

Hello All,


I was curious about NFPA 70E Article 130.5 (D) Equipment Labeling. The article states "Electrical equipment such as switchboards, panelboards, industrial control panels, meter socket enclosures, and motor control centers that are in other than dwelling units and that are likely to require examination, adjustment, servicing, or maintenance while energized shall be field-marked with a label." My question is if you did not account for every "control panel" on the project that was not within your purchase order or clearly labeled on your "scope" of work at the beginning of the project have you violated this code statement? Often times I will have a power systems study where no control panel or remote VFD is shown on the construction drawings for specific mechanical equipment, but may be provided by the mechanical contractor or manufacturer separately from the electrical install. Am I required to put a label on this equipment even if I was not aware of it or didn't define it in the scope of my equipment evaluation on my study. I would think that if a contractor had an energized work permit to work on equipment live and the equipment (maybe a control panel or remote VFD) did not have a label on it they would not touch it until further consultation. Thank you again for your help.


Best Regards,
Engineer in Training

 

[publicgood]

My question is if you did not account for every "control panel" on the project that was not within your purchase order or clearly labeled on your "scope" of work at the beginning of the project have you violated this code

To be clear, 70E is not a code - it is a standard.

The use of this standard is a conversation with the owner. It would be unusual to place arc flash labels with incident energy or the like on all control panels. For those, simply satisfying the NEC requirement in 110 with a general arc flash label is typically most appropriate.

Keep in mind: 70E has one perform an updated study every (5) years, or after a major system change. There is a cost to performing a study and maintaining labels; not to say, if the conversation with the owner concludes their operating procedures need more then general labels, it isn't prudent to have a detailed study.

 

[Sunny_92]

To be clear, 70E is not a code - it is a standard.

The use of this standard is a conversation with the owner. It would be unusual to place arc flash labels with incident energy or the like on all control panels. For those, simply satisfying the NEC requirement in 110 with a general arc flash label is typically most appropriate.

Keep in mind: 70E has one perform an updated study every (5) years, or after a major system change. There is a cost to performing a study and maintaining labels; not to say, if the conversation with the owner concludes their operating procedures need more then general labels, it isn't prudent to have a detailed study.

Simply put, this is probably your best advice.

I perform a lot of arc flash studies and have been in your situation before. IMO, if the control panels are not included in your scope of work, then you are not obligated to label them, but you should have a conversation with the owner about whether they desire them to be labeled or not. If there is any likelihood that someone will need to get into a control panel while it is energized, I believe it should be included with the study and labeled.

I do my best to identify these situations during the bidding process, and having a clear scope of work in your proposal helps out later on. In situations where I find only a few control panels that weren't included in the scope of work, I typically include them in the study and label them as a courtesy. If the number of control panels outside the scope of work is substantial, it usually prompts a conversation with the owner about a possible change order.

 

[PE (always learning)]

Thanks again for your responses. I agree with you both that it should be a conversation with the owner before the project starts and that a solid proposal will clearly define what needs to be labeled. My only issue is that there are some instances where the construction drawings might show an elevator control panel, but no information is given on what kind of equipment is being used or what the AIC rating of that equipment is. I know that the elevator control panel might be a piece of equipment that could be worked on while energized, but the contractors sometimes never give me the shop drawings or provide the data that I need. In this situation would I just put a CYA note that says this control panel should not be field evaluated for adequacy due to lack of information? Does this take away my liability for that equipment and what does the contractor do when he sees equipment in the field that isn't marked?

Best Regards

 

[Jraef]

... In this situation would I just put a CYA note that says this control panel should not be field evaluated for adequacy due to lack of information? Does this take away my liability for that equipment and what does the contractor do when he sees equipment in the field that isn't marked?

Best Regards

All great questions and unfortunately all too common, as EEs get ramped up to speed regarding these, and other labeling (i.e. SCCR) issues. I kind of like your approach, but wouldn't that "should not" be better as "could not"? Saying "should not" might be interpreted as you advising them NOT to look into it and deal with it. "Could not" means you are both informing them of a potential issue, but also absolving yourself of responsibility because it was not in your scope of work.

 

[PE (always learning)]

Thanks for the response. I definitely agree with you that "could not" might be a better choice of words in this situation. For most of my previous studies, I include an equipment evaluation that clearly shows all equipment within the project scope of work that is being evaluated, but I always like to build in a little CYA for grey areas such as the situations described above with control panels. I think I will implement this note in for my new studies.

Best Regards,