do electrical receptacles require an arc flash label

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petersonra

petersonra

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Just curious what the thinking is here.

I ran across a plant where they labeled all the receptacles that were above 120V, but none of the 120V receptacles.
 
Never seen labels on receptacles. Do not think it is required.

110.24 Available Fault Current.
(A) Field Marking. Service equipment in other than
dwelling units shall be legibly marked in the field with the
maximum available fault current. The field marking(s) shall
include the date the fault current calculation was performed
and be of sufficient durability to withstand the environment
involved.
 
petersonra said:
Just curious what the thinking is here.

I ran across a plant where they labeled all the receptacles that were above 120V, but none of the 120V receptacles.
Click to expand...

Funny thing is depending on conditions, there could be more potential incident energy at a 120 volt receptacle than at some other receptacle.

Kind of goes back to the "its only 110" train of thought, yet there are likely more serious accidents and deaths involving 120 volts than most any other voltage because it is not respected well enough.
 
petersonra said:
Just curious what the thinking is here.

I ran across a plant where they labeled all the receptacles that were above 120V, but none of the 120V receptacles.
Click to expand...

First remember labiling deals with shock protection as well as flash protection.

Eight years ago companies only labeld the stuff mentioned in the NEC (i.e. swichboards and big panels). NFPA70E was changed to say that labels are required 'everywhere'. Many of our present studies, now include labels for 'local disconnects'.

The decision on what equipment/locations needs to be labeld is pretty grey. For the most part it boils down to: If someone may interact with the item in a manner that causes harm, they need to be made aware of the situation by adequate labeling.

Other than for large portable equipment (e.g. mobile CAT scanners and other stuff >60A), I don't remember doing receptacles.
 
it is quite possible to "interact" with a standard receptacle in such a way as to result in harm.

jim dungar said:
First remember labiling deals with shock protection as well as flash protection.

Eight years ago companies only labeld the stuff mentioned in the NEC (i.e. swichboards and big panels). NFPA70E was changed to say that labels are required 'everywhere'. Many of our present studies, now include labels for 'local disconnects'.

The decision on what equipment/locations needs to be labeld is pretty grey. For the most part it boils down to: If someone may interact with the item in a manner that causes harm, they need to be made aware of the situation by adequate labeling.

Other than for large portable equipment (e.g. mobile CAT scanners and other stuff >60A), I don't remember doing receptacles.
Click to expand...
 
jumper said:
Never seen labels on receptacles. Do not think it is required.

110.24 Available Fault Current.
(A) Field Marking. Service equipment in other than
dwelling units shall be legibly marked in the field with the
maximum available fault current. The field marking(s) shall
include the date the fault current calculation was performed
and be of sufficient durability to withstand the environment
involved.
Click to expand...

fault current has little to do with arc flash.
 
don_resqcapt19 said:
How does it not? The incident energy of a arc flash is based on the fault current and the supply side OCPD clearing time.
Click to expand...

it is not entirely unrelated but more fault current does not mean more incident energy.

in any case what the poster mentioned was about marking service equipment for its available SCC, which is not the same thing as putting an arc flash label on it.
 
petersonra said:
it is not entirely unrelated but more fault current does not mean more incident energy.

in any case what the poster mentioned was about marking service equipment for its available SCC, which is not the same thing as putting an arc flash label on it.
Click to expand...
what "poster":?

There is a difference between marking something with available fault current and simply marking it with a caution that an arc flash hazard may exist, as well as electric shock or electrocution hazard warnings.
 
petersonra said:
post #2
Click to expand...

That post did not answer your OP question. Marking equipment with available fault current and marking it with a warning that potential arc flash hazards exist are not the same thing.

There is a NEC requirement to mark certain equipment with arc flash warning and the quoted 110.24 is not it. It is in 110.16, it gives examples of some intended equipment to be marked but does not specifically include or exclude any specific equipment to be marked either. It is worded similar and about as confusing as working clearances of 110.26 as far as just exactly what does it apply to.
 
When I/we bring a building into compliance with 70E for arc flash labeling, all SE gear, panelboards, xfmrs, MCCs, and disconnects will be labeled. It's a pretty safe bet that by the time you're at a receptacle it's HRC 0, so no label's needed.
John M
 
petersonra said:
it is not entirely unrelated but more fault current does not mean more incident energy.

in any case what the poster mentioned was about marking service equipment for its available SCC, which is not the same thing as putting an arc flash label on it.
Click to expand...

kwired said:
what "poster":?

There is a difference between marking something with available fault current and simply marking it with a caution that an arc flash hazard may exist, as well as electric shock or electrocution hazard warnings.
Click to expand...

Sorry, brain fart when I posted. For some reason I thought someone at the plant went overboard applying that new labeling requirement in the 2011.

Someday I will learn to read more closely before posting.:ashamed1:
 
mayanees said:
When I/we bring a building into compliance with 70E for arc flash labeling, all SE gear, panelboards, xfmrs, MCCs, and disconnects will be labeled. It's a pretty safe bet that by the time you're at a receptacle it's HRC 0, so no label's needed.
John M
Click to expand...

why would no label be required just because it is HRC 0? If a label is required, it is required regardless of the incident energy level. I know most of us tend to see HRC 0 as "no" arc flash hazard, and as a practical matter that is what it amounts to, but if it is required to be labeled it needs a label that says what the hazard level is.
 
petersonra said:
why would no label be required just because it is HRC 0? If a label is required, it is required regardless of the incident energy level. I know most of us tend to see HRC 0 as "no" arc flash hazard, and as a practical matter that is what it amounts to, but if it is required to be labeled it needs a label that says what the hazard level is.
Click to expand...

The tiny little spark of an ignitor is still an arc flash - just with a very small incident energy level.
 
mayanees said:
It's a pretty safe bet that by the time you're at a receptacle it's HRC 0, so no label's needed.
John M
Click to expand...

There is no exemption that permits not labeling something. If any hazard exists, even a shock from >50V, employees need to be 'warned'. Actual procedures need to be part of each company's Electrical Safe Work Practices program, as NFPA70E is a 'do this' not a 'do it this way' set of guidelines.
 
kwired said:
The tiny little spark of an ignitor is still an arc flash - just with a very small incident energy level.
Click to expand...
Note that I suggested there was no actual hazard, not that there was no potential for a small flash to occur. Just that it would present no actual hazard.
 
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