UL Releases New Edition of UL 1685 Standard for Vertical-Tray Fire Test

Optical-Fiber Cables photoUL has released a new edition of UL 1685, the standard for “Vertical-Tray Fire-Propagation and Smoke-Release Test for Electrical and Optical-Fiber Cables.” The 4th edition can be purchases on the UL website. This new edition is being issued to reaffirm approval as an American National Standard. No changes in requirements are involved.


“4.1 The UL flame exposure is a vertical-tray fire test for determining values of cable damage height and smoke release from electrical and optical-fiber cables when the cables are subjected to a flaming ignition source. For a cable to be acceptable under the UL test procedure, each of the following is to be exhibited (see 10.1 and 10.2):
a)    The cable char height is to be less than 8 ft, 0 inch (244 cm) when measured from the bottom of the cable tray in accordance with Section 8.

b)    The total smoke released is to be 95 m2 or less.

c)    The peak smoke release rate is to be 0.25 m2/s or less.

4.2 The purpose of this test is to determine flame propagation and smoke characteristics of these cables to qualify the cables for the limited smoke marking.

4.3 This test does not investigate the toxicity of the products of combustion or decomposition.

4.4 This test does not cover the constructional requirements for the cable or any electrical, optical, or other performance requirements for the cable.”

*Description from the UL website.

Photo by dvanzuijlekom

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