# US 5,936,205 A · Communication cable for use in a plenum > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,936,205 A - Document ID: US5936205A - Status: Granted - Kind: A - Application number: 08/742,084 - Filed: 1996-10-31 - Granted: 1999-08-10 - Earliest claimed: 1994-11-10 - Assignees: Alcatel - Inventors: Kerry Newmoyer - Web page: https://patentgrep.com/patent/US5936205A ## CPC - H01B 7/295: using material resistant to flame - H01B: CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES (selection for magnetic properties H01F1/00; waveguides H01P {; printed circuits H05K}) ## Abstract A communication cable includes at least one twisted pair of electrical conductors each having a surrounding layer of electrical insulation formed from fluroethylenepropylene (FEP) and at least one additional twisted pair of electrical conductors each having a surrounding layer of electrical insulation formed from an olefin based compound. The cable includes a cable jacket encasing the at least one twisted pair and the at least one additional twisted pair of electrical conductors. The cable meets or exceeds the requirements of the Underwriter's Laboratory UL Standard 910 Test Method For Fire and Smoke Characteristics of Cables Used In Air-Handling Spaces. ## Claims ### Claim 1 A communication cable for use in a plenum, said cable comprising: at least one twisted pair of electrical conductors, each of said electrical conductors of said at least one twisted pair having a single surrounding layer of electrical insulation formed from a first material which is fluroethylenepropylene (FEP); at least one additional twisted pair of additional electrical conductors, each of said additional electrical conductors of said at least one additional twisted pair having a single surrounding layer of electrical insulation formed from a second material which is an olefin based compound; a cable jacket encasing said at least one twisted pair and said at least one additional twisted pair; and wherein said cable meets or exceeds the requirements of the Underwriter's Laboratory UL Standard 910 Test Method for Fire and Smoke Characteristics of Cables Used in Air-Handling Spaces. ### Claim 2 (depends on 1) The communication cable as claimed in claim 1 wherein said second material is a highly brominated and antimony trioxide filled HDPE blended with HDPE. ### Claim 3 (depends on 1) The communication cable as claimed in claim 1 wherein said second material is a hydrated mineral filled polyolefin copolymer HDPE. ### Claim 4 (depends on 1) The communication cable as claimed in claim 1 wherein said cable jacket is formed from an ethylene-trichlorofluoroethylene. ### Claim 5 (depends on 1) The communication cable as claimed in claim 1 wherein said cable jacket is formed from a polymer alloy. ### Claim 6 (depends on 5) The communication cable as claimed in claim 5 wherein said cable jacket is formed from a polyvinylchloride. ### Claim 7 (depends on 1) The communication cable as claimed in claim 1 wherein said at least one twisted pair and said at least one additional twisted pair of electrical conductors have different twist lengths. ### Claim 8 (depends on 7) The communication cable as claimed in claim 7 wherein said at least one twisted pair has the shortest twist length. ### Claim 9 (depends on 1) The communication cable as claimed in claim 1 wherein said second material is a flame-retarded polypropylene (FRPP) base insulation material. ### Claim 10 (depends on 9) The communication cable as claimed in claim 9 wherein said flame-retarded polypropylene base insulation material is blended with either polyethylene or high-density polyethylene. ### Claim 11 (depends on 1) The communication cable as claimed in claim 1 wherein said olefin based material is filled with flame retardant and char enhancer to minimize smoke and flame evolution. ### Claim 12 (depends on 11) The communication cable as claimed in claim 11 wherein said olefin based material contains between 0 and 5 parts per hundred antimony trioxide flame retardant. ### Claim 13 (depends on 11) The communication cable as claimed in claim 11 wherein said olefin based material contains between 0 and 30 parts per hundred halogen flame retardant. ### Claim 14 (depends on 13) The communication cable as claimed in claim 13 wherein said halogen flame retardant is a brominated flame retardant. ### Claim 15 (depends on 14) The communication cable as claimed in claim 14 wherein said brominated flame retardant is decabromodiphenyloxide. ### Claim 16 (depends on 11) The communication cable as claimed in claim 11, wherein said flame retardant is a chlorinated flame retardant. ### Claim 17 (depends on 11) The communication cable as claimed in claim 11, wherein said olefin based material contains lubricants, waxes or stearates, and stabilizers. ### Claim 18 (depends on 1) The communication cable as claimed in claim 1, wherein said olefin based material contains between 50 and 150 parts per hundred mineral filler. ### Claim 19 (depends on 18) The communication cable as claimed in claim 18, wherein said mineral filler is magnesium carbonate. ### Claim 20 (depends on 18) The communication cable according to claim 18, wherein said mineral filler is magnesium hydroxide. ### Claim 21 (depends on 11) The communication cable as claimed in claim 11, wherein said char enhancer is selected from the group including silicate char enhancers, polytetrafluroethylene (PTFE), nitrogen-phosphate or ammonium-polyphosphate. ### Claim 22 (depends on 11) The communication cable as claimed in claim 11 wherein said at least one twisted pair and said at least one additional twisted pair of electrical conductors have different twist lengths. ### Claim 23 (depends on 22) The communication cable as claimed in claim 22 wherein said at least one twisted pair has the shortest twist length.