These requirements cover Nos. 14 - 4/0 AWG single-conductor PVC-insulated and -jacketed underground feeder and branch-circuit cable and flat multiple-conductor PVC-jacketed underground feeder and branch-circuit cables containing two or three Nos. 14 - 6 AWG (for Nos. 4 - 4/0 AWG@ see 1.4) PVC-insulated circuit conductors with or without a grounding conductor. These Type UF cables are intended for use in accordance with Article 339 and other applicable parts of the National Electrical Code in wiring systems operating at a potential of 600 V or less. Deep-well pump cables and multiple-conductor assemblies to which a type-letter designation is not assigned are also covered in these requirements.Multiple-conductor cable that is marked "UF-B" has a 75??(167?? jacket and conductors with insulation of 90??(194?? dry and at least 60??(140?? wet locations. Multiple-conductor cable that is marked "UF" has a 60??(140?? jacket and conductors with insulation for 60??(140?? dry and wet locations. Single-conductor cable is marked "UF" and has an integral insulation and jacket for 60??(140?? dry and wet locations. The ampacity of all cables covered in these requirements is that of 60??(1 40?? conductors.These requirements do not cover insulation other than PVC@ round cables containing two or more circuit conductors@ flat cables containing more than three circuit conductors@ or multiple-conductor cables containing circuit conductors larger than No. 6 AWG - all of which are covered by the National Electrical Code.Multiple-conductor Nos. 4 - 4/0 AWG Type UF cables are acceptable if the results of an investigation conducted in accordance with the intent of these requirements demonstrate that the cables are for the intended use.A product that contains features@ characteristics@ components@ materials@ or systems new or different from those covered by the requirements in this standard@ and that involves a risk of fire or of electric shock or injury to persons shall be evaluated using appropriate additional component and end-product requirements to maintain the level of safety as originally anticipated by the intent of this standard. A product whose features@ characteristics@ components@ materials@ or systems conflict with specific requirements or provisions of this standard does not comply with this standard. Revision of requirements shall be proposed and adopted in conformance with the methods employed for development@ revision@ and implementation of this standard.