Arc Flash

Concerning existing buildings and homes -
When is an arc flash study required and when is it not required?

Thank you for your insight.

Beyond a home inspection.

Are you having a bad day Roy? :slight_smile:

jmassey, what are you doing that requires you to have a concern about arc flash?

Unless you want a condescending answer, you need to be specific in your question.

Thank you David I deserved that , but he is referring to a study and I thought that took an electrical engineer.

Just picking at you Roy!
I’m less stressed out today, thank you! :slight_smile:

Good link. Now if we can figure out why there is high voltage in a residential building…

Ain’t that the truth!

jmassey has asked a lot of questions most above what a home Inspector does .

Ok. guys - sorry.

I am hearing ALOT of people talk about arc flash studies and have seen at least one person recommend an arc flash study (commercial building) as being required by code.

I really do not know about it nor where it is required.

I thought that you gentlemen certainly know more about it than me.

I do not want to say that anything is required in my reports unless I know more about it. This is my first step in trying to know more about it. I certainly will not take another inspectors blanket statement as truth without further review when I have not heard of it being required.

Thank you for your insight.

Fixed for you Roy :smiley:

And by the way, I was a member of InterNachi for many years and have just lapsed this year.

You guys seem to be trying to just poke fun and belittle people of whom you know nothing. Pulling up all of someone’s posts and talking about them. Do you think the leaders of the organization would be happy about that? Do you think that will help persuade me to re-join or persuade others to join?

I happen to know that the people that run InterNachi attest to very high standards of ethics and conduct. This was started to help people.

There is no context because I am asking generally for all existing buildings (commercial and separately residential).

Is there a (possibly new) code requirement for an arc flash study of all buildings or some building irregardless of condition or age? If only some buildings, then what buildings?

If you know about it - and it is not required by code for residential, then please say what the code is and why it does not apply.

If you know about it - and it is not required by code for some commercial buildings, then please say describe something about what the code reference is and why it may apply in some applications and not others.

If you do not know about, then you really should not answer.

Thank you for your insight.

Why distinguish between residential and commercial, low or high voltage arc flashes? Most/all utilities have some type of 240/120 Volt Single-Phase Electrical Work Safety Program designed for companies working in the residential market. There are arc dangers within the scope of a home inspector. I’ve attached one I found on the Internet. PPE for home inspectors inspecting electrical systems and components. Be safe.

Sorry if you are offended .But you seemed to have felt keeping your NACHI membership was to little advantage to you.
But You seem it is OK for you to come and ask the NACHI members to take their time and give you info.
Pulling up your past post’s show others just how often you come and ask questions .
You will also see many have tried to help you .
Rejoining NACHI is your choice
,I do not see where any one has poked fun at you but if they have just maybe you deserved it .
I wish you all the best … Roy

Thanks Ben.

FYI. I have found the correct answers through no help here.

There is some mention in OSHA concerning arc flash labeling.

There is an NFPA requirement for arc flash labeling in certain circumstances. I would tell you what they are, but you appear to know them already. You also appear to already know when to require an arc-flash study in your report when you do not see the label because it is required in certain circumstances.

Good day.

I would prefer that this whole line of discussion be removed because there is no information here that helps anyone.

Don’t worry jmassey1, if the members of NACHI would like to know everything they need to know about Available Fault Current and Arc-Flash labeling and ratings I am here to assist them. Also you really can’t request anything because this is an open forum so rather than perpetuate the lack of information being posted here you might start by actually posting something helpful.

Also in terms of the NFPA, The guidance that is given in Section 110.16 refers to Arc-Flash Hazard Warnings in other than dwelling units. The majority of the home inspectors here would not validate the presence of such a label in a residential dwelling application.

More importantly the requirements of 110.9 and 110.10 are indeed extremely important for home inspectors to be aware of (I could do a whole class on that topic) because sellers who are DIYers tend to make changes to systems that possibly could affect the interrupting ratings of electrical equipment as well as the necessary short-circuit ratings of the said various equipment.

There are a few times that electrical engineers,. keeping in mind that electrical engineers are not the only individuals who can do this, would do what is called a short-circuit study when trying to determine things like selective coordination or just coordination as well as determine the available fault current at various locations down stream of the service to ensure AIC ratings and SCCR ratings are adequate.

Here is a nice quote from that may explain it a little better towards your original question.

"An arc flash study (sometimes called an arc flash analysis or a hazard analysis) is an on-site study of your facility, conducted by a trained expert qualified to evaluate your electrical system and note areas that could present a risk to your personnel or equipment. The study will produce a report containing suggestions and instructions to keep your workers safe and to improve and maintain your electrical system. The report will recommend appropriate personal protective equipment (PPE) for your workers, and suggest adjustments you can make to reduce your workers’ exposure to arc flash hazards.

OSHA 1910.132(d) requires the employer to “assess the workplace for hazards.” Arc flash is one of the electrical hazards recognized by OSHA and NFPA 70E - 2012. NFPA 70E - 2012 article 130.5 requires an arc flash hazard analysis calculation be performed with the only exception being use of 70E tables, if you meet the table parameters. It usually requires an engineering evaluation to determine if you can use the tables."

so basically the arc flash study is not something an HI is generally going to be concerned with but the AIC and SCCR ratings found in 110.9 and 110.10 are indeed something the HI needs to be aware of. The reason I state this is because I assume you are an HI as a potential applicant.

The good news about arc-flash warning labels is that under the 2014 NEC the labels can now be applied via the factory. This happened in previous codes but the local AHJ’s would read the phrase " shall be field marked" and not allow the factory applied warning labels…now the factory labels are considered fine.

Hope you found this helpful…

Good luck
.Sorry you are sad with our lack of information you could use .

Looks like you are satisfied with getting the information elsewhere .
Unfortunately it looks like you are too selfish to post the info here so others can gain more knowledge .
NACHI love to share and help others obviously it looks like you are different and are above helping all.
Wish you well and hope you do come back and share information with all… Roy C

What Paul said!

But I am here now jmassey1 if you have any additional questions…I am more than happy to make your experience here with NACHI a pleasant one. Ask away my friend.

My phone or email is always open to NACHI members…but ONLY NACHI members.

UPDATE: I should mention however, if you do not feel I am qualified to answer your electrical questions please accept my apologies as quite possibly I am just uneducated on all things electrical;)

Ok. At least now you guys are being funny.

And thank you Paul for actual good information.

In reply for the great informative response. I will act in kind.

In an existing building, the labeling (therefore triggering a study) must be completed if the equipment is going to be worked on hot.

So if you are in a commercial facility and you pass people working on the hot panels while you are there, and it is not labeled, then you should mention it in the report. This may be true in residential as well - I defer to Paul.

Will this happen? Probably not, but it is a requirement of NFPA 70E for those circumstances.

At least now we all know.