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I think the fundamental problem here is that IEEE 516 standard was poorly written until the 2009 edition in which it essentially required gloves for everything. 70E and OSHA merely echo 516 so to get to a "shock protection standard", go right for the source (IEEE 516).
So the question seems to presuppose that rubber gloves are being worn and that they MUST be worn for all energized work. This is not true and not the intent of the various codes from what I can see. Older versions of IEEE 516 (prior to 2009) definitely did state this but newer versions do not say this.
There are two types of insulation systems...primary, and secondary. Primary insulation is essentially the part that is supposed to be doing all the heavy lifting. For example when standing on a grounded concrete floor and working inside an electrical enclosure with gloves, the gloves are the primary insulation. Additional layers that are added are secondary insulation. For example, wearing gloves while using insulated tools or a hot stick makes the gloves secondary insulation. In the csae of working from a bucket truck with a hot stick, then the bucket truck mast becomes secondary insulation and the hot stick is primary. How you achieve this is secondary.
The subtle issue is that when multiple insulation systems are used, then we add their voltages and/or resistances to arrive at the overall rating, right? NO. Both are insulators to be sure, but what we actually have is conductive surfaces connected by insulators, which means that in reality, they are capacitors connected in series. We generally don't know and can't control the capacitance. So we need to make sure that EVERY layer has at least a high enough voltage rating to withstand the maximum voltage because the voltage will divide based on the (unknown) capacitances.
IEEE 516 gives almost a dozen work methods to achieve the necessary insulation. Among them includes:
1. Insulated tools.
2. Insulated gloves.
3. Insulated aerial lifts (boom trucks, etc.).
4. Cover up (blankets, line hose, etc.).
5. Bare hands methods, which invert the energized/ground relationship.
NFPA 70E, section 130.4 covers shock protection requirements. Section 130.4(C) lists 3 techniques, and gloves and insulated tools are mixed together in 130.4(C)(1). It does not specify one versus another. Clearly ANSI Z10 and the "hierarchy of controls" would specifically require insulated tools, insulated aerial lifts (with bare hands techniques), and cover up to be the primary means of protecting against shock if equipment must be exposed. These are substitution methods to eliminate shock, whereas making equipment not exposed is elimination (preferred). An EEWP is an administrative control and also preferred. Gloves and/or sleeves are PPE, subject to occasional failure, and should only be used if other methods of eliminating or reducing exposure are not available.
Section 130.7 describes PPE. Section 130.7(C)(7) requires insulated gloves when there is a danger of shock. Since it is located here, then obviously other methods were not available. This would only be true if other shock protection techniques, including insulated tools, did not eliminate the shock hazard.
The point is that gloves and sleeves should be the LAST resort, not the FIRST resort. Gloves should only be used when another technique is not available. 70E definitely does not require insulated gloves if other shock protection techniques are available. In fact, this would be silly. You can't get a glove rated above around 40 kV so if an industrial facility has 69 kV incoming equipment which is typically worked on either with hot sticks or bare hands techniques, the gloves have to come off anyway. Even as secondary insulation, they are not acceptable if they are not rated equal to the full line-to-ground voltage. Before anyone suggests that this is distribution work and that 70E would not apply anyways, I have electrostatic precipitators running at 50-60 kV rectified DC, which is a pretty common working voltage.
The real rub is working below 300 V. The science says that the critical gap before a flashover occurs is down to around 0.1 mm, which is less than the thickness of most gloves of any kind including leather. Thus we see 70E-110.4(B)(4) requiring dry hands, and many safety rules and standards call for clean, dry leather gloves. A dry leather glove has more than enough insulation resistance but the glove test requires the glove to be immersed in water and hi potted...thus, leather gloves can never be voltage rated to meet the ASTM test standard.
However, using insulated tools (screw drivers, wrenches, etc.) at 300 V or less is the same as using a hot stick. The tool is insulated so that it cannot cause a phase-to-phase or phase-to-ground fault, insulated from the user, and includes finger guards to prevent slipping down the handles and coming into contact with live parts.
If that is not the intent, then 130.4 needs to be rewritten to state that voltage rated gloves must be used whenever exposed, energized conductors are present in the work space. Do not mention any other means of reducing or eliminating the hazard because those would be engineered solutions eliminating the exposure.
Note that I do recognize that the line referring to bare hands, live line work was removed from the 2015 draft. I see this as partly good, partly bad. It is a good thing because the intended scope of 70E was also lowered down to 15 kV and less (draft table values have been decreased from 35 kV to 15 kV for arc flash) and because bare hands techniques are almost unheard of below triple digit territory (115 kV and above...rarely at 69 kV), which is totally outside the realm of almost all industrial users (I'm an exception...incoming is 230 kV directly off Duke East's transmission system). I was getting tired of explaining what it is since almost anyone in utilization and even some in distribution have never heard of or seen live line, bare hands work. The downside is if there are some plants (such as mine) where bare hands techniques might actually be used.
The solution that I would recommend is:
130.4(C) should specify that a shock protection risk analysis should be performed when there is exposed, energized conductors. The analysis can either make use of the recommendation in 130.4(C) or use another method. 130.4(C) can simply require rubber gloves. Then an informational note can refer to IEEE 516 for guidance on doing a shock protection risk analysis.
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