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 Post subject: Lineman's Glove Liners
PostPosted: Mon Jul 29, 2013 10:58 am 
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Could someone please explain how/if is this okay?

I want to purchase some 100% cotton liners I found on Salisbury's website. However, when I enter the part number into the supplier's website, they instead offer cotton/polyester blend lineman's glove liners... o_O

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NFPA-70E 130.7(9)(c) says that meltable fibers such as acetate, nylon, polyester, polypropylene and spandex shall not be permitted in underlayers (underwear) next to the skin.
Exception: An incidental amount of elastic used on nonmelting fabric underwear or socks shall be permitted.


While I understand that rubber insulating gloves worn with leather protectors provide significant protection, arc flash analysis is typically calculated based on the distance to the person's face/chest (18"), but the hands are usually much closer to source and thus an increased thermal exposure.


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PostPosted: Mon Jul 29, 2013 7:18 pm 
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The rule against nonmeltable fibers does not necessarily mean that you must avoid any and all synthetic fibers. In fact one in particular (rayon) has excellent thermal properties and though it is not recognized as acceptable by 70E, it is listed as acceptable under NESC. And some of the clothing on the market carrying an ATPV rating even has small amounts of nylon. So it's not that you can't categorically use synthetic fibers. It's that you have to do your homework with anything other than cotton, wool, and I'll even add rayon to this list.

All polymers tend to melt right around 220-265 C, though there is a wide variation here. So by itself when we are concerned with skin getting to 140 F (67 C), this doesn't seem to make much difference. But once polymers do melt or at least flow, they quickly eliminate any air voids between your skin and the polymer and cause major damage. With natural fibers, they will char starting at around 120 C but they don't ever melt so the air spaces between the skin and the natural fibers remains, and ignite at around 350 C. And how they flow makes all the difference in the world.

So this is where you have to do your homework. You need to contact a vendor to find out more information if you are thinking of using a particular type of PPE.

As for the hands issue...remember that the arc flash PPE requirements are generally written with the goal in mind of keeping someone alive. They are not specifically intended to prevent injury. Statistically 2nd and 3rd degree burns on the fingers, arms, and legs are quite survivable. Not so survivable on the chest/face. We don't have enough data to determine where the "walks away unharmed" threshold is at.


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PostPosted: Thu Aug 01, 2013 6:25 am 
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I agree with Paul on this. A King, what is your reason for the liners? We have purchased the Salisbury liners and have them available for our electricians. My experience has been to only use them when you will be gloved up for extended periods of time to absorb sweat. This should not occur very often since we should be de-energizing circuits before working on them.


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PostPosted: Thu Aug 01, 2013 8:01 pm 
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It is quite often (and sometimes all day) if you are a lineman in a utility that uses rubber glove method a lot. Many utilities have a policy of wearing gloves from "cradle to cradle" or "ground to ground" (whenever aerial), irrespective of voltage or other conditions.



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PostPosted: Tue Aug 06, 2013 1:19 pm 
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The use of glove liners is a matter of preference; some folks don't like the feel of wearing just the rubber gloves, and some say the gloves are just easier to take on/off when wearing liners, others prefer to use glove dust, and most of us don't use anything additional.

I did contact the vendor but was quite unimpressed with their response which was basically,"because the glove that is worn over the liner provides protection from voltage, the liner does not need to be 100% cotton". I will just look for another supplier that carries what I want.

We are an industrial facility and we changed our build spec quite a few years ago to specify all finger-safe components inside panels to eliminate the shock hazard. We also started segregating the 480V components(separate panel)from the 24V controls in all new equipment we build. However, we also have older equipment in which there were plenty of exposed energized parts. Our company policy is to always perform a shock hazard analysis upon opening the cabinet door, and if there are any exposed energized parts >300V to wear gloves when inside (the entire panel). We started a component guarding initiative a while back and instead of creating a ton of work orders it was left it to the electricians – your choice, guard it or glove up. We don’t do much live work, but we do lots of troubleshooting.


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PostPosted: Thu Aug 08, 2013 3:32 pm 
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Purists in the field always promote 100% organic fibers. The truth is that the vast majority of "100% cotton" still has a residual of synthetic fibers in the manufacturing because if you have ever gone into a glove liner factory you would see multiple braiders, knitters and sewing operations with piles of product being processed without much segregation in the atmosphere. So unless your NASA, it would be prudent to allow a minimum of synthetic fiber to exist within your liners. Several years ago (20+) ASTM looked at establishing a standard for liner gloves as well as surgical cotton sleeves to be worn under lineman's rubber sleeves. A couple of the larger utilities (Houston L&P and Commonwealth Edison, I think), ran tests and tried to ignite cotton glove liners inside rubber gloves without success. No history of injuries involving glove liners was found at that time. No standard was promulgated. I have stocked the Perfect Fit brand 100% unpolished cotton liners with 2" elastic cuff for 30+ years without any problems-except that Perfect fit was purchased by a line of owners ending up with Honeywell- who has dropped the perfect fit brand and merged them into their other brands. I'll have to find another brand since Honeywell doesn't like to play with the little guys. Magid sent me a pair that are similar but about half the weight. An Outfit named Bodine Business Products sent me samples from their Pakistani manufacturer that are well made and very light, closely woven string knits that resemble military inspection gloves. Half are polished (bleached white) cotton and half are the unpolished cotton string knits. Sizing ran a little small though. If you are concerned (i.e. using a liner under a class-oo glove with very high, long duration fault current potentials), I suggest testing your own liners with a propane torch to see if they (1) self-extinguish after the flame is removed, (2) no melting or dripping occurs and (3) that the remnants are loose carbon soot that could be removed from a burn area without scrubbing with a brush! Liners are worn throughout the day by rubber glove users. I suggest buying them by the dozens, change them out daily and washing them WITHOUT USING THE DRYER, because they are guaranteed to shrink, otherwise the kids will inherit them. Liners give thermal insulation in winter and sweat absorption in summer. Several of my customer believe that cotton liners increase your grip inside rubber gloves. Glove dust is a ground-up mineral - talc - and can assist in getting leather protectors to slide over rubber gloves as well as inside rubber gloves to reduce that sticky texture that sweaty gloves can have. As the above comments show, you can't always depend on the local supplier to give you the same product you purchased in the past, so do due-diligence and verify what you get for $.70 per pair.


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PostPosted: Mon Aug 12, 2013 10:37 am 
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Synthetic fibers will keep a hand warmer in cold but are not as forgiving to absorb perspiration. Synthetics will "mold" to the hand better. Natural fibers are the opposite which wearers tend to sway to the synthetics in cold environments and natural in hot environments. When exposed to flame, synthetics melt whereas natural fibers burn.

When a burn/melt environment happens, burns are treated. As synthetics have melted onto the hand, removing the melted fibers are "adding insult to injury". Cold is not comfortable but neither is having melted fibers peeled off a burn.

It "wasn't that long ago" when ASTM started allowing synthetic fibers to be utilized for glove liners. Having worked the safety aspect of this topic for nearly three decades, my "official" response is "6 of one/half dozen of the other, but having been a victim of an electric blanket (while sleeping) incident... I personally do not suggest synthetics". Cold is not fun, and wearing a lineman glove seems to enhance the refrigeration process. I understand the want for synthetics. I normally display both sides of this topic. The choice is an individual one.


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PostPosted: Mon Aug 19, 2013 12:49 pm 
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From May through September in Virginia and south it only takes a short time to produce moisture in your gloves. Using all cotton liners with the fingers cut out allows easy glove removal, allows maximum dexterity, and doesn't spread powder around. Powder spreading is frowned upon in a pharmaceutical plant.


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PostPosted: Fri Aug 23, 2013 7:15 am 
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I think I like the fingers cut off idea.


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PostPosted: Mon Aug 26, 2013 8:46 am 
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A King wrote:
I think I like the fingers cut off idea.


Me too. I will try this.


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PostPosted: Wed Aug 28, 2013 8:12 am 
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I am the Technical Director for National Safety Apparel, a US manufacturer of FR & AR PPE (amongst several other PPE). We do carry a FR rubber glove liner made from 100% FR cotton knit - this is the same fabric we use in our 12 cal, HRC2 knit shirts.
If you're interested, contact one of our reps in your area and reference the G16PG glove: www. thinknsa .com/Contact_Us/NSA_Sales_Team


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PostPosted: Thu Jan 09, 2014 10:58 am 
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Why would it matter what material is under the rubber gloves? If the rubber gets too hot it will melt anyway. Otherwise it is not going to allow heat to transfer through it to the poly liners...


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PostPosted: Sun Jan 12, 2014 8:05 am 
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The natural rubber chars, not melting. Rubber undergoes vulcanization. There are writeups and photos of this. The ATPV is above 40 cal with leather protectors, even with the colored synthetic variety. Polyester and polypropylene in particular melt at a particularly low temperature (130-140 F) and this can occur INSIDE the glove while the glove itself survives.


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PostPosted: Tue Jan 14, 2014 8:23 am 
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PaulEngr wrote:
The natural rubber chars, not melting. Rubber undergoes vulcanization. There are writeups and photos of this. The ATPV is above 40 cal with leather protectors, even with the colored synthetic variety. Polyester and polypropylene in particular melt at a particularly low temperature (130-140 F) and this can occur INSIDE the glove while the glove itself survives.



That makes sense. Thank you very much!


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PostPosted: Mon Jan 20, 2014 11:19 am 
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A production worker in an iron foundry in New Jersey wore nitrile liner gloves under his aluminized fire gloves in the melt shop. At that time there were no company rules forbidding this practice, although the safety manager was pretty upset when discovering that this practice was going on after the injury occurred. One day an accident with an oxygen lance and a leaking oxygen line resulted in the tool catching on fire in the worker's hands. The aluminized fire gloves were essentially untouched. However the nitrile glove melted and burned INSIDE the fire glove. The production worker spent several weeks out on disability from burns to his hand as a result. This is of course not arc flash and a totally different industry with completely different conditions but the physics is similar.


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