"A"
"B"
"C",
"D",
"E",
"F",
"G",
"H",
"I",
"J",
"K",
"L",
"M",
"N",
"O",
"P",
"Q",
"R",
"S",
"T",
"U",
"V",
"W",
"X",
"Y",
"Z"
Code of Federal Regulations
Title 47 Part 68.215
(d) Workmanship and material requirements —(1) General. Wiring shall be installed so as to assure that there is adequate insulation of telephone wiring from commercial power wiring and grounded surfaces. Wiring is required to be sheathed in an insulating jacket in addition to the insulation enclosing individual conductors unless located in an equipment enclosure or in an equipment room with restricted access; it shall be assured that this physical and electrical protection is not damaged or abraded during placement of the wiring. Any intentional removal of wiring insulation (or a sheath) for connections or splices shall be accomplished by removing the minimum amount of insulation necessary to make the connection or splice, and insulation equivalent to that provided by the wire and its sheath shall be suitably restored, either by placement of the splices or connections in an appropriate enclosure, or equipment rooms with restricted access, or by using adequately-insulated connectors or splicing means.
(2) Wire. Insulated conductors shall have a jacket or sheath with a 1500 volt rms minimum breakdown rating, except when located in an equipment enclosure or an equipment room with restricted access. This rating shall be established by covering the jacket or sheath with at least 15 cm (6 in) (measured linearly on the cable) of conductive foil, and establishing a potential difference between the foil and all of the individual conductors connected together, such potential difference gradually increased over a 30 second time period to 1500 volts rms, 60 Hertz, then applied continuously for one minute. At no time during this 90 second time interval shall the current between these points exceed 10 milliamperes peak.
(3) Places where the jacket or sheath has been removed. Any point where the jacket or sheath has been removed (or is not required) shall be accessible for inspection. If such points are concealed, they shall be accessible without disturbing permanent building finish (e.g., by removing a cover).
(4) Building and electrical codes. All building and electrical codes applicable in the jurisdiction to telephone wiring shall be complied with. If there are no such codes applicable to telephone wiring, Article 800 of the 1978 National Electrical Code, entitled Communications Systems, and other sections of that Code incorporated therein by reference shall be complied with.
(5) Limitations on electrical signals. Only signal sources that emanate from the provider of wireline telecommunications central office, or that are generated in equipment at the customer's premises and are “non-hazardous voltage sources” as defined in the technical criteria published by the Administrative Council for Terminal Attachments, may be routed in premises telephone wiring, except for voltages for network control signaling and supervision that are consistent with standards employed by the provider of wireline telecommunications. Current on individual wiring conductors shall be limited to values which do not cause an excessive temperature rise, with due regard to insulation materials and ambient temperatures. The following table assumes a 45° C temperature rise for wire sizes 22 AWG or larger, and a 40° C rise for wire sizes smaller than 22 AWG, for poly-vinyl chloride insulating materials, and should be regarded as establishing maximum values to be derated accordingly in specific installations where ambient temperatures are in excess of 25° C:
This is not a complete text of the code, the links are not part of the code. Do not use these 'notes' as a substitution for the Federal Code. Non technical portions have been removed
