Always check the arc flash rating sticker

[romeroduke]

Always check the arc flash rating sticker located on the equipment to determine proper PPE needed to open, inspect, or work on equipment. If there isn't an arc flash rating sticker assigned to that equipment; the technician should refer to NFPA 70E before moving forward.

[samair99]

Always check the arc flash rating sticker located on the equipment to determine proper PPE needed to open, inspect, or work on equipment. If there isn't an arc flash rating sticker assigned to that equipment; the technician should refer to NFPA 70E before moving forward.

What do you guys do when you find a label that says "Dangerous! No Safe PPE exists"?

[Jrmcritical]

What do you guys do when you find a label that says "Dangerous! No Safe PPE exists"?

Funny you bring that up. A particular hospital that we do work for in NYC does not allow that signage or verbiage and will actually remove the pages from their arc flash analysis when this condition exists (which is quite common, as the utility coming in in manhattan contributes around 200kA of fault current.

It was explained to me that by posting the "Dangerous! No Safe PPE exists" labels they cannot allow their in-house or any contracted electrician to operate a switch on that board. By removing that label, the person operating the switch is responsible for determining the appropriate PPE levels.

This brings up a newly arising issue. With the availability of 200kAIC rated circuit breakers, much more distribution will be subject to higher fault currents. With the insane cost of real estate in NYC, many sites are moving away from switch and fuse and going with breakers. By doing this they can significantly reduce the footprint of some switchboards.

[Nick1234]

What do you guys do when you find a label that says "Dangerous! No Safe PPE exists"?

Explain to the customer that we are not allowed to open that while its live. If they want us to IR scan it they should install IR windows.

[romeroduke]

What do you guys do when you find a label that says "Dangerous! No Safe PPE exists"?

We will note the equipment I.D. and calorie level and notify customer that we cannot safely access that equipment without de-energizing it. Recommend to the customer to consider upgrading the current protection of that circuit in order to reduce fault clearing time which will reduce calorie level.

[lovetacoach]

Funny you bring that up. A particular hospital that we do work for in NYC does not allow that signage or verbiage and will actually remove the pages from their arc flash analysis when this condition exists (which is quite common, as the utility coming in in manhattan contributes around 200kA of fault current.

It was explained to me that by posting the "Dangerous! No Safe PPE exists" labels they cannot allow their in-house or any contracted electrician to operate a switch on that board. By removing that label, the person operating the switch is responsible for determining the appropriate PPE levels.

This brings up a newly arising issue. With the availability of 200kAIC rated circuit breakers, much more distribution will be subject to higher fault currents. With the insane cost of real estate in NYC, many sites are moving away from switch and fuse and going with breakers. By doing this they can significantly reduce the footprint of some switchboards.

Someone needs to inform this customer of the standards, if they take that stance and someone gets hurt, they are liable!They are required to provide accurate information for service personnel, they cannot allow service personnel to guess.

(D) Equipment Labeling. 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 containing all the following information:

(1) Nominal system voltage
(2) Arc flash boundary
(3) At least one of the following:
a. Available incident energy and the corresponding working distance, or the arc flash PPE category in Table 130.7(C)(15)(A)(b) or Table 130.7(C)(15)(B) for the equipment, but not both
b. Minimum arc rating of clothing
c. Site-specific level of PPE

[ibeam01]

My company just ordered a 100 cal suit for one of our employees to infrared scan something. I believe he said the arc flash rating was actually higher than this, but he was willing to do it with the new suit. Guess sometimes it's up the employee and how much they trust the equipment they are working with/on.

[SecondGen]

My company just ordered a 100 cal suit for one of our employees to infrared scan something. I believe he said the arc flash rating was actually higher than this, but he was willing to do it with the new suit. Guess sometimes it's up the employee and how much they trust the equipment they are working with/on.

100 Cal suit?! That's like bomb squad level crazy, the shockwave alone would probably disrupt your organs and knock you 10' back on your keister. Not sure I would go for that.

[ibeam01]

Yes, he acknowledged at that point he really wasn't that protected from an actual fault anyway, but the company bought it, so I think they kind of called his bluff. He's not one to back down from a job anyway.

The hood is neat, has the fans on it.

[jts1976]

100 Cal suit?! That's like bomb squad level crazy, the shockwave alone would probably disrupt your organs and knock you 10' back on your keister. Not sure I would go for that.

We recently purchased a 100 Cal suit, and use it for opening switchgear (primarily) during arc flash analysis projects, when we're gathering data. The fans in the hood really are great, but it's still like wearing an oven mitt.

[mayanees]

What do you guys do when you find a label that says "Dangerous! No Safe PPE exists"?

A RED DANGER NO SAFE PPE EXISTS label is a common mistake based on an unenforceable Fine Print Note in the 2009 edition of 70E. That note from 130.7(A) stated: FPN No. 2: When incident energy exceeds 40 cal/cm2 at the working distance, greater emphasis may be necessary with respect to de-energizing before working within the Limited Approach Boundary of the exposed electrical conductors or circuit parts. It was repeated as an Informational Note in 2012.

As a result of this note, power systems analysis software manufactures mistakenly provided templates in their software for RED DANGER labels for anything above 40 calories.
The IN was removed in the 2015 edition.

The RED DANGER label also violates the ANSI Z535 labeling standard as RED DANGER is reserved for "death or injury WILL occur" and that's not the case with arc flash incidents.

So an orange Warning label is appropriate, and safe PPE does exist above 40 calories.

John M

[mayanees]

A RED DANGER NO SAFE PPE EXISTS label is a common mistake based on an unenforceable Fine Print Note in the 2009 edition of 70E. That note from 130.7(A) stated: FPN No. 2: When incident energy exceeds 40 cal/cm2 at the working distance, greater emphasis may be necessary with respect to de-energizing before working within the Limited Approach Boundary of the exposed electrical conductors or circuit parts. It was repeated as an Informational Note in 2012.

As a result of this note, power systems analysis software manufactures mistakenly provided templates in their software for RED DANGER labels for anything above 40 calories.
The IN was removed in the 2015 edition.

The RED DANGER label also violates the ANSI Z535 labeling standard as RED DANGER is reserved for "death or injury WILL occur" and that's not the case with arc flash incidents.

So an orange Warning label is appropriate, and safe PPE does exist above 40 calories.

John M

As I read back over this I realized there was another reason for a 40 cutoff. The old HRC table use to go up to 40 calories for PPE 4. That changed from Hazard Risk Categories to Personal Protective Equipment tables which are only used when the bus is not labeled and the PPE TABLES METHOD is used. So if you're using the tables method, the upper limit is 40 calories, and it must be determined by 130.7 C(15) 2021 edition and the associated tables. 130.7(C)(15) a, b and c.

Incident energy calculations for arc flash labels use Table 130.5(G) and provide PPE criteria for incident energy levels from 1.2-12 and above 12 calories.

So this could have been another reason why the software manufacturer's provided templates stating RED DANGER for IE levels above 40 calories.

[beeksYOW]

This absolutely goes without saying!