There has been some great discussion at this forum regarding the use of rubber insulating gloves when working on voltages 240 V and below. Here is this week’s question:

Do you believe rubber insulating gloves are necessary when voltage testing < 240 V equipment like panels?

• Yes
• No
• It Depends on the Situation

I am a firm believer in repetitive training, and when gloves are required for all voltages above 50V, each time every time, when within the restricted approach boundary (RAB), it is, in effect, training. We are training ourselves and our staffs to wear the gloves like a seatbelt. I've never once needed my seatbelt, but I wouldn't think of not wearing it. I may be more open to a leather covers exception below 240

Our elect. safety SOP requires use of gloves with the following exception.
* Exception: For single phase 120 volt circuits protected by a breaker or fuse rated 30 amps or less, voltage rated gloves are not required for voltage testing provided:
- The test equipment is rated Cat III or Cat IV
- The probes have a guard which prevents the hand from contacting the energized part.
- The only energized parts the hands can come into contact with are those being tested.
- At no time do the hands cross a Restricted Approach Boundary (i.e., within 12 inches of 480 volts or within 1 inch of 240/208/120 volts.

Note that we define the restricted boundary for <= 300 volts to be 1 inch. 70E says "Avoid Contact".

• 130.7 (C)(7)(a) says wear insulating gloves if there is danger of hand injury from electric shock due to contact.
• 130.4 (C) No qualified person shall approach or take any conductive object closer than... restricted approach boundary. Which for 50 to 300 volts is “avoid contactâ€�

Sounds like “depends on the situation� is the appropriate answer.

I originally was a "Yes" on this but "Depends" is probably a better answer, although if a part is exposed, it won't take much to make contact (others alluded to this above).

If you are using insulated tools (meter probes) then 130.7(C)(7) does not apply. Gloves are PPE. They should only be used if you cannot mitigate the shock hazard in the first place. Using PPE as a last resort is a basic safety principle (ALARP). This sounds like some folks that do an arc flash study and totally fail to look for mitigation and think that the solution is PPE rather than fixing the problem every time. Outside of electrical circles, using PPE instead of mitigating the hazard is totally unacceptable. I find that in some cable handling cases gloves are superior to doing 100% stick work. But gloves for everything, knowing that it reduces dexterity, increases likelihood of making mistakes? Knowing that pinholes sometimes go undetected? Sounds like extremely poor safety policy to me.

While I agree that the electrical hazard should be mitigated or removed, in this case the actual process of verifying absence of voltage is the potential shock hazard...which is why we are having this discussion.

We are in the process of deciding this very question at our facility, whether to wear insulated gloves for measuring 120V for industrial control circuits. As a former electrician and now electrical engineer, I could make the argument that wearing gloves for something as simple as using a meter to measure 120 volts in a control panel can introduce the additional hazards of being cumbersome, sweat, etc etc. Currently we wear gloves for anything over 300V as the RAB is 12 inches, and therefore PPE required. However, as others have stated, the table states that for voltage below 300V the RAB is simply "avoid contact". It is also impossible to compare a 5A 120V control circuit with a 60A 120/240V circuit. The electrical hazards are different and the equipment designs are different, so making rules for each should be different.

Obviously we all want to protect our employees and ourselves, but this is a gray area that the NFPA70E committee needs to focus on and make a clear ruling.

Why???

NFPA70E already requires your company to create an Electrical Safe Work Practices policy. In the ESWP your company should address the 'it depends' situations and how your company wants to deal with them.

We don't need more rules, we need to properly use the ones that already exist.

Where is the data that says the bare-handed use of volt meters on 120V L-G is statistically risky, in regards to electrical shock? NFPA 70E says at 120V to just 'avoid contact'; so really, how is the use of 500V rated insulated gloves different than the use of 600V insulated instrument probes?

There is no difference from a shock point of view between a 5 A and a 50 A circuit if the voltages are the same for the most part. Human resistance is still around 1000 ohms (the standard used in IEEE 80) so current is around 120 / 1000 = 120 mA. The available current is well above this so no need to look at circuit impedances. This is too little current to trip without a GFCI. So, no, there is no difference between a 5 A and 50 A 120 V circuit from a shock point of view. Also at around 350 volts/mm, shock is unlikely to penetrate even the thinnest DRY gloves.

I do agree with you that the shock hazard doesn't depend on the ampere rating of the circuit, what I'm getting at is that typically control equipment is designed differently than distribution equipment...and the risk of exposure is different. For instance, a 120/240 distribution circuit breaker panel with covers off has many more exposed energized parts (bus, etc) than a modern control panel with 6mm terminal blocks. The voltage is the same yes, but the touch potential is much less in the control panel. Of course these are in my experiences, and I cannot speak for every type of panel in use. I appreciate the response, a lot of good information.

And our company does indeed have an ESWP, however this is based largely on NFPA70E. I'm not asking for a new rule, per se, I'm asking for a clarification of an existing one.

With regards to your question on the risk data, I'd also like to know these statistics. I would agree that using insulated meter leads/probes does indeed satisfy the "avoid contact" stipulation for 120V.

There is nothing wrong with your ESWP being based on NFPA70E, in fact there are many good things about it. However, NFPA70E is purposely written as a 'What Must Be Done' instead of a 'Do It This Way' manual.

These are some portions that I feel point out the ESWP needs to be customized to each facility, and that 70E alone is not sufficient (my emphasis).

110.3 Electrical Safety Program.
(A) General. The employer shall implement and document an overall electrical safety program that directs activity appropriate for the electrical hazards, voltage, energy level, and circuit conditions.
(E) Electrical Safety Program Procedures. An electrical safety program shall identify the procedures for working within the limited approach boundary and for working within the arc flash boundary before work is started.
(F) Hazard Identification and Risk Assessment Procedure. An electrical safety program shall include a hazard identification and a risk assessment procedure to be used before work is started within the limited approach boundary or within the arc Hash boundary of energized electrical conductors and circuit parts operating at 50 volts or more or where an electrical hazard exists. The procedure shall identify the process to be used by the employee before work is started to identify hazards and assess risks, including potential risk mitigation strategies.

So, it is the responsibility of your ESWP to clarify when gloves need to be worn.