The UL 1685:2020 standard defines a testing procedure for evaluating the flame propagation and smoke release characteristics of electrical and optical-fiber cables when exposed to a flaming ignition source. UL Solutions is your global partner for wire and cable testing for safety, compliance, performance, quality and reliability. For a cable to be acceptable under the UL test procedure, each of the following. 1. 1 These requirements cover single and multiple optical-fiber cables for control, signaling, and communications, rated a minimum of 60°C, as described in Article 770 and other applicable parts of the National Electrical Code (NEC).