UL 4:2004 pdf download

5.3.1 One or more grounding Conductors are acceptable in a cable but are not required. Each grounding conductor shall be either of the same construction as the circuit conductors, or an uninsulated copper or aluminum conductor with or without a paper covering. A maximum of one uninsulated grounding conductor is acceptable in a cable. Each grounding conductor shall be cabled with the circuit conductors and shall be entirely in one locahon in the cable — that is. it shall not be divided into two or more parts cabled separately or distributed helically — and, it insulated, shall be identified as indicated in 17.4. Each grounding conductor shall not be smaller than indicated in Table 5.1 or Table 52. Provision of an uninsulated grounding conductor with or without a paper covering or insulated grounding conductors does not remove the need for the aluminum bonding strip required in 7.6.1.
5.4 Fibrous coverings
54.1 Uninsulated grounding conductor with a paper covering.