Static electricity in fiberglass duct grounding requirements

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nmui

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I'm trying to find out more information on the grounding requirements and testing of the ground for above-ground fiberglass duct. Any help?
 
Remember, Don, the word 'electron' comes from the Greek 'elektron', which means 'amber,' certainly non-conductive. Static electricity is usually produced by, or on, non-metallic substances. Plastic sliding-boards and -tubes in kids' playground toys are often grounded at the rivets to reduce static potential.
 
What is the context? If you have 'non-metallic' conduit being used to carry electrical wires, then there is absolutely no bonding requirement at all.

But if you are doing something like running a massive dust collection system where you have flammable particulates entrained in a gas flow, I bet that there are significant requirements. (Not that I know them.)

You _cannot_ bond something that it totally non-conductive. However at the voltages and currents associated with 'static' electricity, it doesn't take much conductivity to drain away the charge. A few percent carbon fiber mixed in with the fiberglass might be sufficient.

-Jon
 
nmui said:
I'm trying to find out more information on the grounding requirements and testing of the ground for above-ground fiberglass duct. Any help?


In relation to what? Is there a requirement or spec? Any additionally information would help.

As for plastic and static, when I installed my plastic dust evacuation system in my wood shop, I proudly turned the system on for a test run and the hair on my head immedatly stood straight up. I decided to replace the system, so now metal duct is going in, DIY.
 
Larry,
Plastic sliding-boards and -tubes in kids' playground toys are often grounded at the rivets to reduce static potential.
Does it work? I would expect that it only works for a very small area around the conductive part. However it does not take much of a conductive path to prevent the build of of static....the IEEE Green Book says 1,000,000 ohms will do the job, so if the product in question has less than 1,000,000 ohms between the bonded points, there will be no static build up. I would expect the resistance of the plastic slides and the fiberglass pipe to far exceed a 1,000,000 ohms and there will be static build up with product or in the case of the slide people movement.
Don
 
Toilet humor deleted.

Post left in place toward post count.

-George
 
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To answer the questions directly while avoiding any physics, there are no grounding requirements for fiberglass ducts. At least not in the NEC. As for for testing the grounding or bonding of an insulating material, it?s not possible.
 
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