We have a project with return (environmental air) above accessible ceilings, so it is a "plenum."
One of the key client requirements for entry into an isolated/secure area of the project requires dielectric separation/isolation of any metallic conduit at the penetration through that floor-to-ceiling partition, which is also a fire-rated wall.
Does anyone know of such a junction box, threaded coupling, or other approved/listed method or device for penetrating a sealed partition wall above the ceiling in an air plenum...
...but which allows for ONLY the ground/bonding conductor to pass through (it is monitored), but prevents any continuous metal contact between the EMT on either side with dielectric (NO metal-to-metal) isolation?
We found a phenolic coupling for threaded conduit, but it does not specifically indicate UL/FM listing for plenum use...
One of the key client requirements for entry into an isolated/secure area of the project requires dielectric separation/isolation of any metallic conduit at the penetration through that floor-to-ceiling partition, which is also a fire-rated wall.
Does anyone know of such a junction box, threaded coupling, or other approved/listed method or device for penetrating a sealed partition wall above the ceiling in an air plenum...
...but which allows for ONLY the ground/bonding conductor to pass through (it is monitored), but prevents any continuous metal contact between the EMT on either side with dielectric (NO metal-to-metal) isolation?
We found a phenolic coupling for threaded conduit, but it does not specifically indicate UL/FM listing for plenum use...