University of Virginia
Standards for Building Telecommunications Facilities
September 2005[1]
This document establishes standards for the installation of telecommunications facilities in University buildings and supersedes “Recommendations for Telecommunications Wiring Guidelines” issued by the Data Communications Working Group July 11, 1990. While the standards are meant to apply particularly to new construction and major renovation projects, they should also be followed when wiring or rewiring existing buildings whenever it is practical and economically feasible. Information Technology & Communication will act as telecommunications consultant and review the plans for all university construction and renovation projects. In buildings where Health System Computing Services (HS/CS) or Health Services Foundation operate networks, these departments will also act as consultants and review telecommunications plans.
It is recognized that the design process and the allocation of space in all construction and renovation projects is actually a negotiation between all interested parties. These standards provide information for the initial project design. Once the initial phase is complete, ITC and the other consultants will work with the building committee to perform the detailed work and ensure that a modern network infrastructure can be installed. ITC and the other reviewers will always be flexible and make sure that the needs of the building occupants are met at the minimum possible cost.
Reference material used in preparing this document includes the “ElA/TIA[2] Building Telecommunications Wiring Standards”. The standards referred to here are published in six different documents[3], all containing related information from which a complete commercial or residential building wiring system is defined. The University standards take precedence over all others.
Table of Contents
Introduction 1
Telecommunications Closet Specifications 3
Horizontal Wiring Pathways 5
Building Entrance Termination Space 7
Horizontal Wiring Components 8
Building Backbone Cabling 9
Miscellaneous Topics 10
Appendix: Fiber Specifications 11
Appendix: Station Cable Specifications 12
Appendix: Wallplate and Outlet Diagrams 14
Appendix: EIA/TIA Standards Publications 15
1. General
Telecommunications closets house the wiring and electronic equipment that are
used to connect user workstations to the University communications network. These
closets are designed for and intended for the intra-building distribution of centrally
managed telephone, data communications, and video services and in no
instance shall they be used to support other building utilities. Telecommunications closets must
be located so they can be accessed from hallways.
2. Dimensions
Closets serving up to 100 outlet locations shall be 6x8 ft. minimum. In areas
where greater than 100 outlet locations are anticipated the closet shall be
sized on a case-by-case basis. Ceilings shall be 9 ft. minimum in height; no
false ceilings will be allowed. The door shall be a minimum of 36” wide and 80”
high, open outward, and be fitted with a keyed lock. Lock keying should meet
ITC and/or HS/CS specifications as appropriate. A magnetic card system may be
requested in some cases in order to meet a particular requirement.
3.
Interior
Furnishings
Floors, walls, and
ceilings shall be treated to minimize dust. Paint or other surface finishes
shall be of a texture and color such that room lighting is enhanced. Three
walls shall be fitted floor to ceiling with BC grade ¾” fire rated plywood.
4.
Lighting
Lighting shall be a minimum of 50-foot candles measured 3 feet above the
finished floor, mounted 8.5 ft. above the finished floor. No wall-mounted
lighting will be allowed.
5.
AC Power
A minimum of two (2) dedicated 20 amp, 120 volt circuits and one (1) dedicated
30 amp 208/220 volt circuit, outlet NEMA size L14-30-R30A 125/250V shall be
provided. Quad service outlets shall be placed at four (4) ft. intervals along
the length of the four walls and 18 inches above the finished floor. Service
panel location and breaker positions shall be clearly marked. Access shall be
available to the main building-grounding electrode. Power for communications
wiring closets should always be supplied from building emergency power systems
whenever emergency power is available in a building. Some wiring closets in
some buildings will need additional electrical power depending on special
needs. These extra needs will be specified by ITC and/or HS/CS during the
review process.
6.
Environment
Temperature and humidity control shall be continuous over the range 50 to 85
degrees F with 30% to 75% relative humidity non-condensing. The cooling system
should maintain the ambient room temperature of below 75 degrees F. A positive
pressure shall be maintained with an air exchange sufficient to dissipate the
heat generated by electronic/electrical equipment. Dissipated power will
typically be less than 6,000 watts. The cooling system for the wiring closet
must operate on a 24x7 basis, 365 days per year. Wiring closet cooling can not
be controlled by energy management systems that cut off cooling when the
building is not occupied. When additional power is specified per Section 5
above, a corresponding increase in cooling capacity is required.
7.
Closet
Penetrations
Floor penetrations for vertically stacked closets shall be a minimum of two 4”
penetrations per closet. Each penetration will include a bushed sleeve
extending 1” above the finished floor. It is recommended that all penetrations
be in clusters at a location in the closet stack specified by ITC and/or HS/CS.
Penetrations for horizontal conduit or cable tray runs which use ceiling
pathways should be near the 8 ft. level. Additional penetrations may be needed
depending on the density of network devices needed in a particular area.
8.
Closet
Linkage
When multiple closets exist on a single floor, these closets must be
interconnected via horizontal cable pathways. If drop ceilings are used, the
closets should be interconnected using cable ladder that is 12 inches wide and
4 inches deep. In locations without drop ceilings a minimum of two four (4)
inch conduits should be provided to implement the closet interconnection. A
conduit system must include pull boxes at 100 foot intervals and after every
pair of 90° bends. Conduits entering the closet through a 90 degree bend,
whether from floor or ceiling, shall do so with a bend radius of 18 inches for
2’ Inner Diameter (ID) or less. Conduits with greater than a 2” ID shall have a
radius ten times conduit ID. Pull cords shall be provided in all conduits.
9.
Closet-to-Wall
Outlet Distance
The closet-to-wall outlet distance shall be a maximum of 290 cable-feet.
Multiple closets shall be provided where necessary to meet this requirement. Remember
to include the vertical components of a cable path when calculating distances.
The 290 foot limit is cable length and not simply floor path length.
10.
Number of
closets per building
General rule of thumb is one communications closet per 10,000 square ft of
office space.
11.
Fire
Suppression
Wiring closets should not include fire sprinkler heads. If sprinkler heads
must be accommodated, a dry-pipe system is preferred.
1.
General
The term “horizontal wiring” refers to a number of cable types that run from a
communications closet on a particular floor of a building to workstations on
that floor. Where there are multiple closets on a floor, it can also include
wiring-hub interconnection cables. These interconnection cables are typically
some combination of copper and fiber optic cables. Careful design work on the
horizontal cable pathways to minimize total cable length will help to lower
wiring costs and in some cases might decrease the total number of wiring
closets needed to serve a building.
2.
Recognized
Cables
The following cable types are recognized as intra-building horizontal wiring,
see appendix for details.
a) Category 5E and Category 6 twisted-pair cables.
b) RG-6 or equivalent coaxial cables.
c) FDDI-grade 62.5 micron multi-mode and 8 micron single-mode optical fiber cable.
3.
Ceiling CablePathways
Ceilings used as distribution pathways for horizontal cabling shall meet the
following conditions:
a) If a fixed ceiling has to be used as a cable route, properly sized conduit must be installed as a pass through.
Conduit Capacity:
4 inch conduit = 100 Category 5 cables, (50 network drops)
3 inch conduit = 50 Category 5 cables, (25 network drops)
2 inch conduit = 24 Category 5 cables, (12 network drops)
1 inch conduit = 8 Category 5 cables, (4 network drops)
b)
Ceilings of
lay-in tiles which allow easy access to a suitable space above are recommended.
Suitable space is defined as that which supports the installation and ready use
of a 12” open-frame center spine cable ladder. These cable ladders should be
installed in all hallways. Solid bottom cable trays are not to be used.
c)
Height of the
cable ladder/raceway above the finished floor shall be no more than 11’.
d)
Metal cable
ladders/raceways shall be bonded to the building ground per applicable code.
e) Plenum ceilings add to the cost of wiring a building since special type of cable must be used to meet fire codes.
4.
Raceway-to-Outlet
Cable Path
A 1” conduit shall be provided from the cable raceway area
above the ceiling to a quad wall box, or quad boxes if specifically requested,
for each workstation location. The quad box should be fitted with a mud ring
to size it down to use a duplex outlet faceplate. The conduit should be
installed from the outlet box to the cable ladder in main corridor. When no
cable ladder exists, a simple stub termination of the in-wall outlet conduit extending
several inches into the ceiling space is preferred. A cable ladder should be
installed for all addition and renovation projects. Enclosed raceways should
not be installed as this restricts access. Pull ropes shall be installed in
all conduits as part of the conduit installation work. Daisy-chained systems
that originate in the wiring closet and serve multiple outlets via a single
conduit are not allowed.
1.
General
The building entrance room houses the facilities necessary to terminate the
inter-building cable plant and to transition to the intra-building communications
backbone cabling. Along with cable splice facilities, this room will also hold
the lightening surge suppressors needed for the telephone system cable plant. The
intra-building backbone cables run from this room via the vertical riser and
horizontal pathways to the communications wiring closets throughout the
building. In some cases this room may also serve as a wiring closet for the
lower level of the building.
2.
Dimensions
Rooms shall be 6x8 ft. minimum with 8 ft. ceilings. The door shall be 80” high
and 36” wide minimum, open outward, and be fitted with a keyed lock.
3. Interior Furnishings
Floors, walls, and ceilings shall be treated to minimize dust. Paint or other surface finishes shall enhance room lighting. Three walls shall be fitted floor to ceiling with BC grade ¾” fire rated plywood.
4. Lighting
Lighting shall be ceiling mounted and measure 50 foot-candles three feet above the finished floor.
5.
AC Power
Two dedicated 20 amp 120 volt circuits shall be provided. A minimum of one quad
outlet per wall shall be provided. Outlets should be marked with associated
breaker number and location of panel. Access shall be provided to main building
ground electrode. In cases where this room also serves as a wiring closet, the
additional electrical power requirements for a wiring closet must also be met.
6.
Environment
In cases where the Building Entrance room is also acts as a wiring closet, the
cooling specifications for a normal wiring closet must also be met.
7.
Entrance
pathway sizing
The size of the pathways, if any, between the building entrance point and the
Building Entrance room shall be the same as the actual facilities that enter
the building. This is generally two 4” conduits.
8.
Closet
Linkage
A backbone/riser cable pathway having the capacity of two (2) 4” conduits
minimum shall be established between the Building Entrance Facility and one
of the N vertically stacked closets configured as described in Sections 7
and 8 of the Telecommunications Closet Specification portion of this document.
If wiring closets are not stacked and positioned at random throughout a building,
a 12” wide by 4” deep ladder rack shall be provided from the entrance facility
to each closet.
1.
General
Horizontal wiring is that portion of the building telecommunications
infrastructure which supports signal transmission from the telecommunications
closet to the user workstation. Included in this section are the
closet-to-workstation cable, telecommunications closet termination hardware,
and workstation wall outlet hardware.
2.
Closet-to-workstation
Cable Types
Recognized horizontal cable types are Category 5E and Category 6 twisted-pair
cable, RG-6 coaxial cable, 62.5 micron optical fiber, or other special cable
types as specified by ITC and/or HS/CS. See appendix.
3.
Installed
cable
Standard practice shall be to install two Category 5E twisted-pair cables from
the telecommunications closet to each outlet location. Coax and/or fiber shall
be installed as specified on a case-by-case basis. Horizontal pathways from
closet to the workstation outlets shall be sized to accommodate all three media
types; exposed wiring is not allowed. Some locations may require three
twisted-pair cables per outlet.
4.
Twisted-pair
Closet Terminations
Twisted-pair wiring shall be terminated in the telecommunications closet using Avaya
110 Cross-Connect System. Data pair cross-connects shall use Category 5E,
Category 6 components, including cordage, and be arranged such that any user
workstation can access any communications hub port. See the appendix for
details.
5.
Twisted-pair
Wall Outlet Terminations
Twisted-pair wiring
wall outlet terminations shall be Category 5E or Category 6 compliant Avaya RJ-45
jacks. The outlet wall plate shall be part of a modular system that supports
twisted-pair, coax, and fiber. See appendix for details. Some locations may
require specialized terminations as specified by ITC and/or HS/CS.
6.
Communications
outlet density
Standard practice shall be to install two (2) communications outlets per 100
sq. ft. of assignable office space. In all other areas, communications outlets
to be provided as required. Interaction with the department that will occupy
the space is essential when determining the number and location of
telecommunications outlets.
1.
General
Building backbone cabling refers to the intra-building
communication trunk system. The system consists of multi-pair telephone riser
cable, coaxial trunk cable, optical fiber cable, and in some cases Category 5E
or Category 6 twisted pair cabling. These cables bring the various
communications services from the building entrance facility to the
telecommunications closets on each floor from whence they are distributed via
the horizontal wiring systems to the individual user outlets.
2.
Topology
Building backbone cabling shall have a star
topology unless otherwise specified.
3.
Intra-building
Data Backbone
The data network backbone cable installed shall be a combination of 62.5 micron
multi-mode and 8 micron single-mode optical cable. No in-building distance
limitations apply.
4.
Intra-building
Video Trunk
The building video backbone shall be ½”, 75 ohm semi-rigid coax. No distance
limitations apply.
5.
Intra-building
Telephone Riser
Telephone risers shall be unshielded twisted pair CMR rated cable. Two pairs
per 100 sq. ft. of assignable space shall be provided to each floor if the
exact number of telephones required is unknown. If the number of telephones
required is known, allow for 100% growth.
1.
General
This section contains comments on a variety of topics pertaining to building
wiring that do not fit exclusively (at this time) under one of the five main
headings.
2.
Documentation
Documentation shall be computer based and include both schematic and table
forms. Elements of the building infrastructure to be documented shall be chosen
based on local requirements and with reference to the TIA/EIA-606
infrastructure administration standard. A documentation maintenance program
shall be developed and put into effect.
3.
Proximity to
EMI sources
Telecommunications closets and wiring pathways shall not be located in close
proximity to sources of electromagnetic interference. Special attention shall
be given to potential EMI sources such as large electric motors, welding
equipment, etc. Wiring pathways shall be at least 12” from unshielded power
lines of <480 volts and at least 5” from fluorescent lighting fixtures.
|
Intra-building Fiber Cable |
All fiber shall be Corning multimode graded index fiber with a 62.5/125 micron core/cladding diameter, buffered to 900 microns, and housed in a UL, OFNR rated jacket or standard Corning SMF-28e single-mode 8 micron cable. |
Minimum Performance Specifications for Multi-mode cable
|
Wavelength (nm) |
Attenuation (dB/Km) |
Capacity (MHz-Km) |
|
850 |
3.75 |
160 |
|
1300 |
1.5 |
500 |
Approved cable: SEICOR Inc., MIC series fiber optic cable.
Wiring closet-to-workstation cable shall have four (4) twisted-pair and meet all EIA Category 5E, Category 6 specifications.
|
|
Attenuation @ 100 MHz |
Next Loss @ 100 MHz |
|
Minimum Performance Specifications |
67 dB/1000 ft |
32 dB @ 1000 ft |
|
Minimum Approved Cable Types |
|
|
Cable Application |
Approved Cable Model |
|
Normal cable use |
Avaya PDS LAN Cable No. 1061 |
|
Plenum-rated cable use. |
Avaya PDS LAN Cable No. 2061 |
|
EIA/TIA-568 |
Commercial Building Telecommunications Wiring Standard
|
|
TSB-36 |
Technical Systems Bulletin: Additional Cable Specifications for Unshielded Twisted-Pair Cables.
|
|
TSB-40 |
Technical Systems Bulletin: Additional Transmission Specifications for Unshielded Twisted-Pair Connecting Hardware.
|
|
EIA/TIA-569 |
Commercial Building Standard for Telecommunications Pathways and Spaces.
|
|
EIA-570 |
Residential and Light Commercial Telecommunications Wiring Standard.
|
|
EIA-606 |
The Administration Standard for the Telecommunications Infrastructure of Commercial Buildings.
|