StructuredCabling2019
New member
- Location
- canton
I am new to the site. I have a very unusual issue that rarely occurs in the industry and I hope to find a definitive answer to my problem.
I have recently taken over a large low voltage project in an uncontrolled manufacturing space. This facility is a standard open metal frame building with 45’’ ceiling hights. This is an Uncontrolled & unclassified environment meaning there is no HVAC, and no risk of combustion and is nonhazardous. This facility is not a riser or plenum space. There is no class 1,2,3 div or any combination thereof, no combustibility risks. The individual who designed this facility designed it using all HDPE conduit based on the customer's request. The HDPE conduit is installed at 45’ AFF and contains a single 12 strand fiber. As I understand it the HDPE was chosen for several reasons and the HPDE conduit was justified for this installation based on a NEC exception for indoor installations. I have now been engaged to take this project to completion as the previous manager is no longer with the company. In fact, both the individuals (company/customer side) are no longer with their respective companies. The customer side replacement who is now responsible for this project has raised a concern and stated that he fears the facility will fail fire inspection because of the HDPE. Based on the NEC code for HDPE and the exception in the project notes code calls out 504.20. As I understand this exception HDPE can be installed inside if the HDPE supports an intrinsically safe system. The HDPE is in a non-hazardous facility and contains a single fiber cable no voltage. The HDPE is in rigid vertical conduit from the device at the floor level to ceiling height. In the ceiling, the HDPE is exposed and is in j-hooks connected to the red iron in the ceiling at 45’ AFF. The facility has a sprinkler system installed at ceiling height.
I have spoken to several individuals RCDDs, electricians, etc, with many years of industry experience and they all default to NO HDPE inside until I talk about the exception. The exception discussion becomes a “gray” area because HDPE is not typically installed inside under normal circumstances. I have been unable to get a definitive yes or no and I have no real resolution.
I am trying to achieve several different goals.
I would not have designed this facility in this way regardless of it being code simply because of the problems it has created. I have been tasked with a resolution that satisfies all the concerns and any help that can be offered would be greatly appreciated.
I have recently taken over a large low voltage project in an uncontrolled manufacturing space. This facility is a standard open metal frame building with 45’’ ceiling hights. This is an Uncontrolled & unclassified environment meaning there is no HVAC, and no risk of combustion and is nonhazardous. This facility is not a riser or plenum space. There is no class 1,2,3 div or any combination thereof, no combustibility risks. The individual who designed this facility designed it using all HDPE conduit based on the customer's request. The HDPE conduit is installed at 45’ AFF and contains a single 12 strand fiber. As I understand it the HDPE was chosen for several reasons and the HPDE conduit was justified for this installation based on a NEC exception for indoor installations. I have now been engaged to take this project to completion as the previous manager is no longer with the company. In fact, both the individuals (company/customer side) are no longer with their respective companies. The customer side replacement who is now responsible for this project has raised a concern and stated that he fears the facility will fail fire inspection because of the HDPE. Based on the NEC code for HDPE and the exception in the project notes code calls out 504.20. As I understand this exception HDPE can be installed inside if the HDPE supports an intrinsically safe system. The HDPE is in a non-hazardous facility and contains a single fiber cable no voltage. The HDPE is in rigid vertical conduit from the device at the floor level to ceiling height. In the ceiling, the HDPE is exposed and is in j-hooks connected to the red iron in the ceiling at 45’ AFF. The facility has a sprinkler system installed at ceiling height.
I have spoken to several individuals RCDDs, electricians, etc, with many years of industry experience and they all default to NO HDPE inside until I talk about the exception. The exception discussion becomes a “gray” area because HDPE is not typically installed inside under normal circumstances. I have been unable to get a definitive yes or no and I have no real resolution.
I am trying to achieve several different goals.
- To be able to confirm that HDPE as part of an intrinsically safe system while rare can be installed this facility and is neither a code violation nor a fire code violation.
- If the NEC code does not support this HDPE inside as outlined in Art. 504 I need to know why it does not.
- What would ping this installation as a fire code violation?
- If in fact this facility is not code, what are my options? Fire-coating? fire barrier wrapping? Overlaying a split plenum innerduct? (besides the obvious remove/replace of the entire system).
I would not have designed this facility in this way regardless of it being code simply because of the problems it has created. I have been tasked with a resolution that satisfies all the concerns and any help that can be offered would be greatly appreciated.
