For voltage testing, we have to use rubber insulating gloves with leather protectors. When you get above 8 cal/cm2, NFPA 70E switches from "leather gloves" to "arc rated gloves". We know you're not supposed to wear meltable fabric underlayers, but someone questioned the rubber gloves. So two questions related to that.
1) Is there an APTV or other thermal rating for the rubber insulating gloves or something in ASTM D120 that addresses the thermal aspect of the rubber gloves? The concern is, will they melt under a high incident energy arc flash?
2) Are arc rated gloves which can be fabric, acceptable as protectors for rubber insulating gloves?

Thanks,

If you need rubber gloves for shock protection, than that is what you wear for arc flash protection.

I believe there has been some testing done and it is around 40 cal. A search of this forum should result in some information and you could ask the manufacturer of your gloves if they tested them and what the results are.

Hugh's group tested them. They are well above 40 ATPV across the board.

The "arc rated" mitts really only apply when you have a situation where only arc flash and not shock protection is required, and even then you can simply wear the rubber gloves with leather protectors anyways.

These probably aren't kosher but I *might* know someone who wears them while surveying because *he* finds it very difficult to handle small panel cover bolts and screws when wearing leather gloves over rubber gloves. They fit *his* hands well and *he* reports good dexterity with them.

Ansell 12 Cal/cm² PowerFlex 13 Medium Duty Work

http://www.70esolutions.com/ansell-12-cal-cm-powerflex-13-medium-duty-work/

Another pic, this time time an actual close-up:

If you're hinting at shock protection, only a rubber glove will ever pass because of the nature of the test. The test criteria is to fill the glove up to within a couple inches of the end of the cuff and then submerse it in water to the same depth, then hi pot the glove at the required test voltage. Theoretically the leakage (milliamps) matters but in practice gloves that fail the test blow out.

At 120 VAC the insulation required is less than most work gloves. A clean, dry leather glove and most of the knit industrial gloves are plenty thick enough to provide adequate insulation. But they will never pass the "glove test". And even if they don't know why, almost all qualified personnel know that the rubber glove requirement for low voltage control work is just plain silly. If you are turning 3/8" and larger nuts and bolts like a lineman, then they're fine. But it's a too bad that violence in the work place will get you fired because anyone that wants electricians to wear rubber gloves with leather protectors while attempting to use a jeweler size screw driver to attempt to hold a screw, wire, and turn it all to tighten on a terminal for control circuits in years past would receive a proper dose of violence in the workplace.

However I have a solution to the problem of doing this kind of work. Since they make the rules, have the safety manager come down and do the wrench turning while the electrician supervises. The problem will be quickly rectified.

+1

Hi Jeff

Please find attached article originally articled by Hugh Hoagland in 2013. It pretty much says all that the otehrs have stated and some more information.

Hope that this is of some help

Thanks

Hi Jeff

Please find attached PowerPoint slides summarizing the tests that were conducted up here at Kinectrics in Toronto by WH Salisbury. Very interesting results and a good read

ASTM F18 decided not to force the rating of rubber gloves and leather protectors (this was in the days when only two companies in the US really sold D120 gloves.

We have tested several brands but they do not all release data.

Color makes a difference. Black is best. Blue is pretty good and Yellow is too. Red is lowest.

We recommend you use leather protectors for now. ASTM is developing a new standard for AR Protector Gloves but this will not solve the potential issue of igniting rubber (hard to do it below 20 cal but possible in some gloves).

Use Black Class O or higher with a protector glove and there is little risk in most settings. If you need shock protection, rubber is the only option.

The AR gloves are not currently approved for protectors but this could change next year if the committee approves of the standard.

Hugh Hoagland
Sr. Managing Partner
e-Hazard | http://www.e-hazard.com

Data above from Salisbury is the published data. I have done others but only Salisbury publishes to my knowledge.

Many do well but ask your supplier.

Hugh