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COMPUTER NETWORK DESIGN GUIDELINE FOR EXISTING SYSTEMS DOCUMENT NUMBER: 16765 APPLICATION: ELEMENTARY, MIDDLE AND HIGH SCHOOL DATE OF ISSUE: 11-27-06 - First Issued NOTES: The attached guideline should be utilized in the design of modifications to existing computer network systems. ATTACHMENTS: Existing Computer Networking Infrastructure Guidelines, dated 11-27-06 Computer Network Design Guide Existing Systems 1 / 6

EXISTING COMPUTER NETWORKING INFRASTRUCTURE GUIDELINES 11-27-06 PART 1.00 GENERAL 1.01 SCOPE OF GUIDELINES A. The intent of these guidelines is to provide specific requirements for the design and installation and operation of computer networks for Hillsborough County Schools. It is very important for the proper management and maintenance of the School District s computer networks that all the District networks are carefully designed and that proper codes, standards and guidelines are followed in all facilities. These guidelines are not intended to be a system specification and should be used only as a guideline in planning and designing modifications to existing network infrastructure systems. B. Modifications to existing systems shall conform to the requirements for new systems, as described in Standard Document Number 16760 Computer Network Design Guideline for New Systems, unless indicated otherwise in this document. 1.02 EXISTING NETWORKS TO REMAIN Existing networks scheduled to remain may be tested by the Contractor prior to commencement of the work. Upon commencement of the work, all existing network components shall be assumed to be fully functional, unless otherwise documented by test results. Upon completion of the work, existing networks shall operate at the same or better capacity than at commencement. Any existing network component damaged during execution of the work shall be repaired or replaced at no additional cost to the Owner. 1.03 EXISTING NETWORKS TO BE REPLACED Replacement of existing infrastructure shall conform to requirements of Standard Document Number 16760 Computer Network Design Guideline for New Systems 1.04 EXISTING NETWORKS TO BE EXPANDED OR UPGRADED A. Any moves, adds or changes must follow the installation practices identified in section 1.05 B. All existing labeling must be verified and changed to meet the district s labeling standards for data. C. All existing duplex (2) data drops are to be changed to quad (4) data outlets. D. Existing cabling, data jacks or patch panels that do not meet Category 5E specifications must be replaced by Category 5E certified product. E. In occupied spaces, existing open-style data racks must be replaced by new enclosed data cabinets. If space limitations do not allow for the installation of a new data cabinet, a ventilated enclosure must be built around the existing open-style rack. F. The contractor shall protect existing network electronics by removing and storing them in a secure, clean and dry environment. G. All fiber and copper data runs are to have their own path. At no time will fiber optics or data cable be allowed to run in a path or conduit with other existing cables. If Computer Network Design Guide Existing Systems 2 / 6

multiple fibers are to be run in a single 4 conduit, then each fiber must be run in its own innerduct. Innerduct must be a minimum of 1 and must be orange in color. H. At no time is the number of data cables run through a conduit to exceed 40% of the conduit s capacity. I. All fiber must be a home run to MXC. Cross connections are not permitted. J. Any wire mold or surface mounted junction box used on the surface of an interior wall must be attached to the wall by screws. The wire mold must have the capacity to handle six (6) Cat 5E cables for expansion K. Existing and new power poles must be securely anchored to the floor with Tapcons, and be supported above the ceiling by attachment to a permanent, non-moving structure L. Cabling or fiber no longer used do to upgrade or replacement must be removed M. New data racks for an existing network are to be terminated as follows. a. SC type connections are to be used on any new rack and ST at the MXC if the site is ST based and the LIU has the room. b. If the LIU does not have any open space for a new fiber, then an SC style LIU must be used in the rack. c. If there is no room in the rack for another LIU, then the existing LIU must be replaced and all connections will be of SC type connections. 1.05 INSTALLATION PRACTICES A. Routing of Fiber and Data Cabling: In no case will fiber optic cables be permitted to run exposed, and in no case will Category 5 Extended Overhead cabling be permitted to run exposed or to penetrate the exterior envelope of a building. Lashing cables to existing conduits/appurtenances is strictly prohibited. B. Network system design and installation practices must account for proper fire stopping of any penetrations of fire rated assemblies. C. Fire stopping of fire rated assemblies must meet the requirements of UL, NFPA, and all applicable building codes. D. Raceway, cable support and routing requirements: 1. Conduit for fiber optical cable: Fiber optic cabling shall be installed in a raceway, up to the edge of the backboard of the MXC or IXC, at which point it may be exposed only if secure to the backboard. a. Conduits for fiber optic cable shall be two (2) inches, minimum. b. Conduit installed indoors shall be EMT with compression fittings. 2. The raceway is to be routed in concealed, accessible above-ground locations. Where this is determined by the Owner to be inappropriate, raceways may be installed underground and may be direct burial rated Schedule 40 PVC or galvanized rigid steel. A metallic warning tape must be installed twelve inches (12 ) above all PVC. All trenching will be dug by hand at existing facilities, to a depth of thirty-six inches (36 ). Computer Network Design Guide Existing Systems 3 / 6

3. Raceways installed in exposed areas subject to potential damage or harsh conditions shall be galvanized rigid steel. All raceways shall be run straight and level. 4. Exposed raceways are not allowable except where conditions do not allow concealed accessible routing, and only where prior approved by the Owner. All surface-mounted conduit shall be installed with 2-hole straps. E. Conduit for UTP 1. UTP cabling installed inside buildings shall be installed in a raceway from the communications outlet up to the ceiling space (above the dropped ceiling). Unless otherwise approved, this raceway shall be a concealed conduit in the wall, minimum ¾. Where allowed in existing buildings, a surface-mounted wiremold type raceway shall be utilized. Surface mounted raceway shall be mechanically fastened to the wall. Adhesive backing alone will not be permitted. 2. Where a dropped ceiling does not exist, the UTP shall be run in EMT, sized as required. 3. Conduit sleeves, two inches (2 ) minimum, shall be provided at all penetrations of fire rated assemblies. All penetrations shall be fire stopped in accordance with an applicable UL Listed firewall penetration detail using UL Listed fire stopping materials and methods. F. UTP Cabling 1. All communications outlets within a building shall be connected to their respective hub via Category 5 Extended Overhead compliant Unshielded Twisted Pair copper cabling. UTP cabling lengths shall not exceed two hundred seventyfive feet (275 ) from the patch panel to the communications outlet. 2. UTP Cable Routing: UTP should be installed over accessible corridor ceilings or along lines that are parallel to the contours of the building. Deviations from straight should be made at right angles. Wall penetrations or floor penetrations shall be made via pre-constructed distribution systems designed to support and protect the cable. 3. UTP cabling may be free-wired where it is routed concealed above an accessible ceiling. Free-run cables shall be bundled and loosely tie-wrapped at a maximum spacing of twenty-four inches (24 ) on center. Use plenum-rated tie wraps in air plenums. 4. Cabling shall be supported to the building structure at a minimum of four foot (4 ) intervals, with J-Hooks or other approved fittings/means. Cabling shall not be supported from the ceiling, ductwork, conduits, piping, or any other non-structural building member. Two inch (2 ) sleeves shall be provided where the cabling exits the ceiling up to the edge of the MXC or IXC backboard. 5. All UTP cabling must maintain a minimum service loop of four feet (4 ) at both ends for serviceability. At workstation end, service loop must be in ceiling at conduit stub up. At data rack, the service loop for all UTP cables will be attached to backboard or ladder of freestanding racks with appropriate support. 6. Refer to the Educational Specification for number and type of drops to be provided in each space. Computer Network Design Guide Existing Systems 4 / 6

7. Patch cables to activate all drops are to be supplied by the Contractor. Patch cables are to be delivered to the Owner s representative and a signed receipt obtained by the contractor for submittal with the close-out documents. Receipt must note quantities. a. All cables must be yellow in color for data and blue in color for telephone. b. Lengths must be divided evenly between three feet (3 ) and six feet (6 ) for patch panels. c. The same count must be supplied for workstation cables in ten feet (10 ) lengths. 8. Owner will supply fiber jumpers as type of electronics provided may vary, but all bulk heads (LIUs) are to remain as specified elsewhere. G. Grounding 1. All equipment racks, cable trays, surge suppressors and cabinets shall be bonded to the building grounding electrical system, building structural steel and shall have a supplemental driven ground rod. In addition a bare #6 AWG copper wire shall be carried and routed with the fiber backbone outside of the fiber conduit throughout the campus providing a loss resistance grounding system. H. Labeling and Identification 1. Each cable shall be labeled with a unique identifier. All network system components shall be labeled, including rooms, racks, cabinets, patch panels, individual ports in each patch panel, communications outlets, etc. The system identification administration shall meet the requirements of TIA/EIA-606. 2. All communications outlets shall be labeled using an encoded labeling system with the room number and port number. 3. Each patch panel in the MXC and IXCs shall be labeled sequentially left-to-right, top-to-bottom, with the room number and port letter, such that the ports can be located easily on the panel. I. Fiber Optic Cabling 1. All fibers in each fiber optic cable shall be identified at each end on the interconnect cabinet. Fibers shall be identified with the building number and corresponding 1-12 fiber number. It shall be everywhere in minimum of two inch (2 ) conduit, except where field conditions permit a run into a building of less than fifty feet (50 ). If fiber must be run outside, such as under canopies, the fiber should be Berk-Tek Armor jacket 62.5/125, tight buffered, indoor/outdoor riser rated plenum and supported appropriately. All fiber optic runs must maintain a minimum service loop of four feet (4 ) at both ends for serviceability. The service loop for all fiber will be attached to backboard or ladder support of freestanding racks with appropriate support. J. Aerial Fiber Distribution For Portable Buildings 1. This work is by Owner unless specifically directed otherwise. 2. If directed to provide aerial fiber distribution for portable buildings, provide only aerial-rated outdoor-rated fiber optic cable. Use a 6-count fiber cable to each Computer Network Design Guide Existing Systems 5 / 6

portable building. Provide a 6-count fiber cable to the 1 st portable from the nearest IXC. 3. Provide sufficient pole and messenger wire support for the cable. 4. Provide sufficient guying for pole support. Computer Network Design Guide Existing Systems 6 / 6