Design Standards

The Design Guidelines for system development are contained in and found at the UNC-CH Facilities Planning and Construction webpage.
Specific references shall be made to the following Chapters and requirements:
- Chapter V - Division 2 – Site Work, Section 02200 – Earthwork, particularly the Excavation and Backfilling of Utilities Trenches.
- Division 16 – Electrical. This section contains information on Primary (15 kV) duct banks, contractor licensing requirements, site lighting, transformers, and interior electrical as well. etc. There are additional web links within the site lighting and telecommunications sections for more information.

Following are current changes/ additions to these specifications:

All conduits used in duct banks shall be PVC schedule 40 UL listed, to comply with the state requirement for this listing.
The UNC-CH approved duct bank spacer is the Underground Devices, Inc. Wunpeece spacer. Go to the Underground Devices webpage for details. This spacer provides a 3 inch separation from conduits in the same row as well as between rows, but provides a 3 ½ spacing to the trench bottom to comply with UNC-CH requirements.
For each conduit (includes spares), thoroughly clean (rod, clear, swab) and then install a waterproof marking cord. This cord is to be 1/2 inch wide, with a 1250-pound tensile test rating, marked at least every foot, equivalent to NEPTCO Inc. MuleTap Part # WP1250P, without splices or ties of shorter lengths. Only the whole, unbroken length of tape is to be installed in each duct.
The UNC-CH Design Guidelines also contain this requirment: “Plug all conduit entry end points with expandable reusable conduit plugs capable of withstanding 15 PSI minimum hydrostatic pressure.” Select this Conduit Plug link for an example of the type of conduit plugs UNC uses to meet the required guidelines. These are made by Jackmoon USA Inc. a division of Tyco Electronics.