Article 800 General Requirements for Communications Systems
Informational Note No. 1: See 90.2(B)(4) for installations of circuits and equipment that are not covered.
Informational Note No. 3: For further information for fire alarm systems, see Article 760.
Cable Sheath. A covering over the conductor assembly that may include one or more metallic members, strength members, or jackets.
Exposed (to Accidental Contact). A circuit in such a position that, in case of failure of supports or insulation, contact with another circuit may result.
Point of Entrance. The point within a building at which the wire or cable emerges from an external wall or from a concrete floor slab.
Premises. The land and buildings of a user located on the user side of the utility-user network point of demarcation.
Informational Note No. 1: Accepted industry practices are described in ANSI/TIA-568.1-D-2015, Commercial Building Telecommunications Infrastructure Standard; ANSI/TIA-569-D-2015, Telecommunications Pathways and Spaces; ANSI/TIA-570-C-2012, Residential Telecommunications Infrastructure Standard; ANSI/TIA-1005-A-2012, Telecommunications Infrastructure Standard for Industrial Premises; ANSI/TIA-1179-2010, Healthcare Facility Telecommunications Infrastructure Standard; ANSI/TIA-4966-2014, Telecommunications Infrastructure Standard for Educational Facilities; and other ANSI-approved installation standards.
Informational Note No. 2: See NFPA 90A-2018, Standard for the Installation of Air-Conditioning and Ventilating Systems, for discrete combustible components installed in accordance with 300.22(C).
Informational Note No. 3: Paint, plaster, cleaners, abrasives, corrosive residues, or other contaminants may result in an undetermined alteration of wire and cable properties.
Informational Note: Directories of electrical construction materials published by qualified testing laboratories contain many listing installation restrictions necessary to maintain the fire-resistive rating of assemblies where penetrations or openings are made. Building codes also contain restrictions on membrane penetrations on opposite sides of a fire resistance-rated wall assembly. An example is the 600 mm (24 in.) minimum horizontal separation that usually applies between boxes installed on opposite sides of the wall. Assistance in complying with 800.26 can be found in building codes, fire resistance directories, and product listings.
Informational Note: For additional information regarding overhead (aerial) wires and cables, see ANSI C2-2017, National Electrical Safety Code, Part 2 Safety Rules for Overhead Lines.
Exception No. 1: Communications wires and cables and CATV type coaxial cables shall not be required to have a vertical clearance of not less than 2.5 m (8 ft) above auxiliary buildings, such as garages and the like.
Exception No. 2: A reduction in clearance above only the overhanging portion of the roof to not less than 450 mm (18 in.) shall be permitted if (1) not more than 1.2 m (4 ft) of communications service-drop conductors pass above the roof overhang and (2) they are terminated at a through- or above-the-roof raceway or approved support.
Exception No. 3: Where the roof has a slope of not less than 100 mm in 300 mm (4 in. in 12 in.), a reduction in clearance to not less than 900 mm (3 ft) shall be permitted.
Informational Note: For additional information regarding overhead (aerial) wires and cables, see ANSI/IEEE C2-2017, National Electrical Safety Code, Part 2, Safety Rules for Overhead Lines.
Exception: Where a coaxial cable does not have sufficient strength to be self-supporting, it shall be attached to a supporting messenger cable that, together with the attachment fixtures or supports, shall be acceptable for the purpose and shall have sufficient strength to withstand the loads to which they may be subjected.
Informational Note No. 1: For additional information regarding overhead (aerial) wires and cables, see ANSI C2-2017 National Electrical Safety Code, Part 2, Safety Rules for Overhead Lines.
Informational Note No. 2: Specific separation distances may be calculated from the sideflash equation in NFPA 780-2017, Standard for the Installation of Lightning Protection Systems.
Informational Note: Similar bonding conductor or grounding electrode conductor length limitations applied at apartment buildings and commercial buildings help to reduce voltages that may be developed between the building's power and communications systems during lightning events.
Exception: In one- and two-family dwellings where it is not practicable to achieve an overall maximum bonding conductor or grounding electrode conductor length of 6.0 m (20 ft), a separate ground rod meeting the minimum dimensional criteria of 800.100(B)(3)(2) or (B)(3)(3) shall be driven, the bonding conductor or grounding electrode conductor shall be connected to the ground rod in accordance with 800.100(C), and the ground rod shall be connected to the power grounding electrode system in accordance with 800.100(D).
Informational Note: Informational Note Figure 800.100(B)(1) illustrates the connection of the bonding conductor in buildings or structures equipped with an intersystem bonding termination or a terminal block providing access to the building grounding means.
Informational Note Figure 800.100(B)(1) Illustration of a Bonding Conductor in a Communications Installation.