Q: Could an end user wear a 12" high voltage protector over a Class 00/0 14" rubber glove?
The difference between a 13″ Class 00/0 protector and a 12″ Class 1-4 protector is the cuff color.
A: Some companies will not allow this because they want the protector cuff cover to indicate that the glove is high voltage.
But there is nothing to prohibit this practice. The prohibition is having the protector too long. Higher class protectors do have ONE difference, thickness of the leather. Higher voltage gloves require the minimum thickness of the leather to be more.
For protector lengths see our NFPA 70E Low Voltage Training slide below.
If a protector is too long, the flash-over distance will be compromised. Then the rubber insulating glove meeting ASTM D120 will be compromised in providing protection from shock.
Wear protector gloves meeting ASTM F696-2019. This specification covers leather protectors for rubber insulating gloves and mittens. Check the length of the protector glove to assure it isn’t too long.
When we do onsite NFPA 70E Compliance Electrical Safety Audits or evaluate electrical safety written programs (required by OSHA law), we look for this specifically. It is a common misunderstanding in training that doesn’t fully filter into the written program. Many workers think, “A longer protector gloves will protect my rubber glove better,” not thinking about the flashover issue. Makes sense when you think it out.
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The guiding document here is ASTM F696. There is nothing in this document about cuff color. There is, however, specific guidance regarding the leather thickness. In Section 4.1.1 it states “The thickness of the leather in the hand portion shall not be less than 1.00 mm (0.039 in.) nor greater than 1.60 mm (0.063 in.). For protectors for Class 0 gloves, the leather must be provided in a minimum thickness of 0.58 mm (0.023 in.),
with the maximum thickness being 1.2 mm (0.04 in.). For protectors for Class 00 gloves, the leather must be provided in a minimum thickness of 0.40 mm (0.016 in.) with a maximum thickness being 1.20 mm (0.047 in.).” So only a high-voltage protector with leather between 1.00 mm and 1.2 mm could be used over a low-voltage rubber insulating glove, with the proper cuff clearance, and still be in compliance with ASTM F696.
That’s right Richard. Nothing requiring cuff color but many use it to identify HV protectors. Using the HV protector would make the gloves harder to use but the length is often what people don’t think about.
Leather materials are not electricity-conductive, so they can act as an insulator. We can use leather gloves as one of the safety components for electrical work.
This is a dangerous practice to depend upon leather as an insulator of any type. Leather is not rated whatsoever, and if wet or dirty, can create even more of a serious shock hazard. Ask any welder – they will not weld in wet leather gloves. Always use a proper voltage-rated glove as required in OSHA or local safety laws according to where you live. This is why regulations require retesting of gloves every 6 months – to ensure that they haven’t been punctured or damaged.
Do rubber gloves prevent electric shock? The answer is yes if the rubber gloves are designed for electrical use. But for usual rubber gloves, this function is not reliable or even non-existent.
Yes – the gloves must be tested per the ASTM standard as stated. A normal rubber glove, like a dishwashing glove for example, has no official “rating” whatsoever, and is not to be trusted with one’s life. Only properly-rated, tested, and pre-inspected gloves offer shock protection.
The Occupational Safety and Health Administration (OSHA) requires the use of electrical gloves for electric work. Depending on the electricity’s voltage, there are different classes of electrical gloves to choose from, including 00, 0, 1, 2, 3, and 4.
Very true, Robert. OSHA regulations follow ASTM D120 & ASTM F496. Gloves are rated by glove classification as you mention – Class 00, Class 0, and Classes 1 through 4. The main glove chart in OSHA can be found by scrolling to the bottom of this web page: https://www.osha.gov/laws-regs/regulations/standardnumber/1910/1910.137
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Thank you for the kind words. I hope you have a great 2023!