UL 1651

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Optical Fiber Cable
UL 1651
1 Scope

1.1 These requirements cover single and multiple optical-fiber cables for control, signaling, and communications as described in Article 770 and other applicable parts of the National Electrical Code (NEC). Cables complying with these requirements are:Type OFNP - Plenum - A nonconductive cable for use in ducts, plenums, and other spaces used for environmental air. A nonconductive cable contains no metallic members and no other electrically conductive materials.Type OFCP - Plenum - A conductive cable for use in ducts, plenums, and other spaces used for environmental air. A conductive cable contains non-current-carrying conductive members such as metal strength members and metallic vapor barriers.Type OFNR - Riser - A nonconductive cable for vertical use in shafts or from floor to floor.Type OFCR - Riser - A conductive cable for vertical use in shafts or from floor to floor.Type OFN and OFNG - General Purpose - Nonconductive cables for general purpose use.Type OFC and OFCG - General Purpose - Conductive cables for general purpose use.

1.2 Smoke and fire considerations are as follows for the cables covered in these requirements:

• a) TYPE OFNP and OFCP CABLES - Cables that are intended for installation in accordance with Section 770.154 (A) of the National Electrical Code (ANSI/NFPA 70) in a duct, plenum, or other space used to transport environmental air without the cable being enclosed in a raceway in that space are tested for smoke and flame characteristics in accordance with the National Fire Protection Association Standard Method of Test for Flame Travel and Smoke of Wires and Cables for Use in Air-Handling Spaces, ANSI/NFPA 262. A cable that complies exhibits a maximum flame-propagation distance that is not greater than 5 ft, 0 in or 152 cm, a peak optical density of smoke produced of 0.50 or less (32 percent light transmission), and an average optical density of smoke produced of 0.15 or less.
• b) TYPE OFNR and OFCR CABLES - Cables that are intended for use in vertical runs in a shaft, or that penetrate more than one floor, in accordance with Section 770.154 (B) of the National Electrical Code, ANSI/NFPA 70, are tested for flame-propagation characteristics in accordance with the Test for Flame Propagation Height of Electrical and Optical-Fiber Cables Installed Vertically in Shafts, UL 1666. A cable that complies has a flame-propagation height less than 12 ft, 0 in or 366 cm and temperatures are 850.0°F (454.4°C) or less at a height of 12 ft, 0 in or 366 cm.
• c) TYPE OFN, OFNG, OFC, and OFCG CABLES - Type OFN and OFC cables are intended for installation in accordance with Section 770.154 (C) or (D) of the National Electrical Code, ANSI/NFPA 70, comply with a 70,000 Btu/h (20.5 kW) vertical-tray flame test. The cable manufacturer chooses one of the following tests:
• 1) The UL test described in 9.2.1 and 9.2.2 of these requirements. These paragraphs apply the test described as the UL Flame Exposure (smoke measurements are not applicable) in the Standard for Vertical-Tray Fire-Propagation and Smoke-Release Test for Electrical and Optical-Fiber Cables, UL 1685, to cable that is surface marked or designated by a marker tape as "OFN" or "OFC".
• 2) The FT4/IEEE 1202 test as described in 9.3.1 of these requirements, which applies the test method described as the FT4/IEEE 1202 Type of Flame Exposure (smoke measurements are not applicable) in the Standard for Vertical-Tray Fire-Propagation and Smoke-Release Test for Electrical and Optical-Fiber Cables, UL 1685. This test differs from the UL tests in loading (more cables are used, with small cables bundled, and the spacing between cables or bundles is limited), burner angle, and failure criterion.

Type OFCG and OFNG cables are to comply with the FT4/IEEE 1202 test.

1.3 Cables covered in these requirements are not required by the NEC to be used in raceway. These cables are capable of use without the physical protection of raceway but may be pulled into conduit or installed in other raceway.

1.4 The overall jacket on a cable that has "sun res" or "sunlight resistant" in a surface marking or on a marker tape complies with a 720-h sunlight-resistance test.

1.5 These requirements do not cover cables that contain current-carrying conductors. Requirements for cables that contain electrical and optical fiber members are found in the applicable standard for the electrical cable.

1.6 These requirements do not cover the optical performance of the cable.