Structured Cabling Standards and Codes 899
Both the TIA and the EIA are accredited by the American National Standards Institute
(ANSI, section 6.2.7) to develop voluntary industry standards for a wide variety of
telecommunications products. This means that many standards often are labeled ANSI/
TIA/EIA. The various committees and subcommittees of TIA/EIA develop standards
for fiber optics, user premises equipment, network equipment, wireless communications,
and satellite communications.
Although there are many standards and supplements, the following are used most
frequently by cable installers (see Figure A-14).
Figure A-14 TIA/EIA Structured Cabling Standards
■ TIA/EIA 568-A is the Commercial Building Standard for Telecommunications
Wiring. The standard specifies minimum requirements for telecommunications
cabling, recommended topology and distance limits, media and connecting hard-
ware performance specifications, and connector and pin assignments.
■ TIA/EIA-568-B is the Cabling Standard. This standard specifies the component
and transmission requirements for media. TIA/EIA-568-B.1 specifies a generic
telecommunications cabling system for commercial buildings that will support
a multiproduct, multivendor environment. TIA/EIA-568-B.1.1 is an addendum
that applies to four-pair unshielded twisted-pair (UTP) and four-pair screened
twisted-pair (ScTP) patch cables bend radius. TIA/EIA-568-B.2 specifies cabling
components, transmission, system models, and the measurement procedures
appen_a.fm Page 899 Tuesday, May 20, 2003 4:54 PM
900 Appendix A: Structured Cabling
needed for verification of twisted-pair cabling. TIA/EIA 568-B.2.1 is an adden-
dum that requirements for Category 6 cabling.TIA/EIA-568-B.3 specifies the
component and transmission requirements for an optical fiber cabling system.
■ TIA/EIA 569-A is the Commercial Building Standard for Telecommunications
Pathways and Spaces. The standard specifies design and construction practices
within and between buildings that are in support of telecommunications media
and equipment.
■ TIA/EIA-606-A is the Administration Standard for the Telecommunications

Infrastructure of Commercial Buildings, including cable labeling standards. The
standard specifies that each hardware termination unit must have some kind of
unique identifier. This standard also outlines the requirements for record keeping
and maintaining documentation for administering the network.
■ TIA/EIA-607-A is the standard for Commercial Building Grounding and Bonding
Requirements for Telecommunications. It supports a multivendor, multiproduct
environment, as well as the grounding practices for various systems that might be
installed on customer premises. The standard specifies the exact interface points
between the building grounding systems and the telecommunications equipment
grounding configuration, and specifies building grounding configurations needed
to support this equipment.
European Committee for Electrotechnical Standardization
CENELEC is known in English as the European Committee for Electrotechnical
Standardization. It was set up in 1973 as a nonprofit organization under Belgian law.
CENELEC develops electrotechnical standards for most of Europe; it works with 35,000
technical experts from 19 European countries to publish standards for the European
market. It has been officially recognized as the European standards organization by the
European Commission in Directive 83/189/EEC. Many CENELEC cabling standards
mirror ISO cabling standards, with minor changes.
Although CENELEC and the International Electrotechnical Commission (IEC) operate
at two different levels, their actions have a strong mutual impact because they are the
most important standardization bodies in the electrotechnical field in Europe. Cooper-
ation between CENELEC and the IEC is described in what is known as the Dresden
Agreement, approved and signed by both partners in that German city in 1996. This
agreement was intended to expedite the publication and common adoption of interna-
tional standards and accelerate the standards preparation process in response to market
demands. This agreement also was intended to ensure rational use of available resources.
Therefore, full technical consideration of the content of the standard preferably should
take place at the international level.
N

O
TE
For more informa-
tion on CENELEC,
visit www.cenelec.org.
appen_a.fm Page 900 Tuesday, May 20, 2003 4:54 PM
U.S. Codes 901
International Organization for Standardization
The International Organization for Standardization (ISO) is an international organiza-
tion composed of national standards bodies from more than 140 countries. For example,
the American National Standards Institute (ANSI) is a member of the ISO. The ISO is
a nongovernmental organization established to promote the development of standard-
ization and related activities. The ISO’s work results in international agreements, which
are published as international standards.
The ISO has defined a number of important computer standards, the most significant
of which is perhaps the Open Systems Interconnection (OSI) model, a standardized
architecture for designing networks.
U.S. Codes
For some networking projects, a permit is required to ensure that the work is being done
properly. Contact local zoning departments for information on permit requirements.
To obtain copies of local or state building codes, contact the building official for the
local jurisdiction. All of the basic building codes—CABO, ICBO, BOCA, SBCCI, ICC,
and so on—that are adopted throughout the United States can be purchased from the
International Conference of Building Officials (ICBO).
It is common for codes requiring local inspection and enforcement to be incorporated
into state or provincial governments, and then possibly down to city and county
enforcement units. Building codes, fire codes, and electrical codes are examples. Like
occupational safety, these were originally local issues, but disparity of standards and
often lack of enforcement has led to national standards. When adopted by state or
local authorities and enforced to appropriate levels, these standards then are turned

over to the lower-level authorities for implementation.
Note that violating these codes often can be expensive in both penalties and delayed
project costs.
Some codes are enforced variously by city, county, or state agencies. This means that a
project within the city would be handled by the appropriate city agencies, while those
outside the city would be covered by county agencies. For instance, fire codes can be
enforced by the county building permit department in some communities but by the
local fire department in others.
Although local entities inspect and enforce the codes, they often do not write them.
Standards-making organizations frequently do that for them. For instance, the National
Electrical Code is written to sound like a legal ordinance. This makes it possible for
NOTE
For more informa-
tion on the ISO, visit
www.iso.org/iso/en/
ISOOnline.frontpage.
NOTE
The Americans with
Disabilities Act (ADA)
has led to several
important changes
in new construction,
alterations, and
renovations regard-
ing networking and
telecommunications.
Depending on the use
of the facility, these
changes might be
mandatory, and fines

can be assessed for
failure to comply.
appen_a.fm Page 901 Tuesday, May 20, 2003 4:54 PM
902 Appendix A: Structured Cabling
local governments to adopt the code by vote. This might not happen regularly, and the
government might fall behind. Always know which version of the NEC is in force for
your area.
Evolution of Standards
As network bandwidth has increased from 10 Mbps to 1000 Mbps and beyond, it has
created new demands on cabling. Older types of cable are often inadequate for use in
the faster modern networks. For this reason, the types of cabling used changes over time,
and the standards reflect this. The following are the standards for TIA/EIA 568-B.2:
■ For twisted-pair cables, only 100-ohm Category 3, 5e, and 6 cables are recognized.
Category 5 cable no longer is recommended for new installations and has been
moved from the body of the standard into an appendix. Category 5e or greater is
now the recommended cable for 100-ohm twisted-pair cable.
■ The Category 6 standard specifies performance parameters that ensure that prod-
ucts meeting the standard are component-compliant, backward-compatible, and
interoperable between vendors.
■ When terminating Category 5e and higher cables, the pairs shall not be untwisted
more than 13 mm (0.5 in) from the point of termination. The minimum bend
radius for UTP horizontal cabling remains four times the cable diameter. The
minimum bend radius for UTP patch cable is now equal to the cable diameter
because it contains stranded wires and thus is more flexible than solid-core
copper cables used in horizontal cabling.
The acceptable length of patch cords in the telecommunications room has changed
from 6m to 5m (19.7 ft. to 16.4 ft.) at maximum. The acceptable length of a jumper
cable in the work area has changed from 3m to 5m (9.8 ft. to 16.4 ft.) at maximum.
The horizontal segment distance remains at 90m (295.3 ft.). If a MUTOA is used, the
work-area jumper can be increased in length if the horizontal length is decreased a

corresponding amount to keep the total link segment length not longer than 100m
(328.1 ft) (see Figure A-15).
The use of a MUTOA or consolidation point also mandates a separation of at least
15 meters (49 ft) between the TR and the MUTOA or consolidation point in order
to limit problems with crosstalk and return loss.
N
O
TE
Most countries have
similar systems of
codes. Knowledge
of these local codes
is important if you
are planning to do a
project that crosses
national boundaries.
appen_a.fm Page 902 Tuesday, May 20, 2003 4:54 PM
U.S. Codes 903
Figure A-15 Changes to Horizontal Cabling Standards
All patch cords and cross-connect jumpers formerly were required to use stranded cable
to provide the flexibility needed to survive repeated connection and reconnection. The
wording around this topic now has been changed from shall to should regarding stranded
conductors. This allows solid conductor cord designs.
Patch cords are critical elements in the network system. Language regarding the onsite
manufacture of patch cords and jumpers still allows these cables to be created, but it
now is strongly encouraged that network designers purchase cables that are premade
and have been tested.
Category 6 and Category 7 are the newest copper cables available. Because Category 6
cable is used more frequently, it is important for cable installers to understand its benefits.
The significant difference between Category 5e and Category 6 is the means used to

maintain the spacing between the pairs inside the cables. Some Category 6 cables use a
physical divider down the center of the cable. Others have a unique sheath that locks
the pairs into position. Still other Category 6 cables use a foil screen that overwraps
the pairs in the cable. The latter type of cable often is called screened twisted-pair
cable, or ScTP.
To achieve even greater performance than Category 6, Category 7 cables that are avail-
able use a fully shielded construction that limits crosstalk among all pairs. Each pair is
enveloped within a foil wrap, and an overall braided sheath surrounds the four foil-
wrapped pairs. A drain wire might be provided in future cables to facilitate grounding.
Work Area
Field
Test
Instrument
Begin Permanent Link
Optional Transition/Consolidation
Point Connector
Telecommunications
Outlet/Connector
Telecommunications Room
End Permanent Link
Field
Test
Instrument
Horizontal
Cross-Connect
or Interconnect
Legend
Test Equipment Cord
Optional Transition Cabling
Cable Between Outlet/Connector or

Transition/Consolidation Point
Connector and Horizontal
Cross-Connect
Test Equipment Cord
Maximum Length
G + H
90 m (295 ft)
F
G
H
I
FG
H
I
appen_a.fm Page 903 Tuesday, May 20, 2003 4:54 PM
904 Appendix A: Structured Cabling
Standards for the structured cabling will continue to evolve. The focus will be on
supporting the new technologies that are converging on the data network, such as the
following:
■ IP telephony and wireless utilizing a power signal in the transmission to provide
power to the IP phones or access points.
■ Storage area networking utilizing 10 GB Ethernet transmission
■ Metro Ethernet “last mile” solutions that require optimizing bandwidth and
distance requirements
The standard for Power over Ethernet (PoE) is under development and will be available
in the near future. PoE embeds a power signal on cables used for Ethernet transmissions.
This power signal is used to free IP phones and wireless access points from the need for
connection to AC power outlets, simplifying deployment and reducing costs.
Safety
Safety is an important concept containing information that often is overlooked in cov-

erage of low-voltage telecommunications wiring. Students not accustomed to working
in the physical workplace will benefit from labs and training. Other important safety
topics include these:
■ Safety codes and standards for the United States
■ Safety around electricity
■ Lab and workplace safety practices
■ Personal safety equipment
Safety Codes and Standards for the United States
Most nations have rules designed to protect workers against hazardous conditions.
In the United States, the organization charged with worker safety and health is the
Occupational Safety and Health Administration (OSHA). Since the agency was created
in 1971, workplace fatalities have been cut in half and occupational injury and illness
rates have declined 40 percent. At the same time, U.S. employment has nearly doubled
from 56 million workers at 3.5 million worksites to 105 million workers at nearly
6.9 million sites.
It is OSHA’s responsibility to protect workers by enforcing U.S. labor laws. Technically,
OSHA is not an agency related to building code or building permits. However, OSHA
inspectors have the power to impose heavy fines and to shut down a job site if they find
serious safety violations. Anyone who works on or is responsible for a construction
N
O
TE
For more informa-
tion on OSHA, visit
www.osha.gov.
appen_a.fm Page 904 Tuesday, May 20, 2003 4:54 PM
Safety 905
site or business facility needs to be familiar with OSHA regulations. The organization
offers safety information, statistics, and publications on its website.
MSDS

A material safety data sheet (MSDS) is a document that contains information on the
use, storage, and handling of a hazardous material. It provides detailed information on
the potential health effects of exposure and how to work safely with the material. It
tells what the hazards of the material are, how to use it safely, what to expect if the
recommendations are not followed, what to do if accidents occur, how to recognize
symptoms of overexposure, and what to do if such incidents occur.
Underwriters Laboratories, Inc.
Underwriters Laboratories, Inc. (UL), is an independent, nonprofit product safety test-
ing and certification organization. UL has tested products for public safety for more
than a century. The UL focuses on safety standards but has expanded its certification
program to evaluate twisted-pair LAN cables for performance according to IBM and
TIA/EIA (Telecommunications Industry Association/Electronic Industries Alliance)
performance specifications, as well as National Electrical Code (NEC) safety specifica-
tions. The UL also established a program to mark shielded and unshielded twisted-pair
LAN cables, which should simplify the complex task of making sure that the materials
used in the installation are up to specification. Listing by UL denotes initial testing and
periodic retesting to ensure continuing conformance to standards.
The UL tests and evaluates samples of cable and then, after granting a UL listing, con-
ducts follow-up tests and inspections. This independent testing and follow-through
make the UL markings valuable symbols to buyers.
The UL LAN Certification Program addresses not only safety, but also performance.
Companies whose cables earn these UL markings display them on the outer jacket
(Level I, LVL I, or LEV I, for example).
National Electrical Code
The purpose of the National Electrical Code (NEC) is to safeguard persons and
property from hazards arising from the use of electricity. This code is sponsored by
the National Fire Protection Association (NFPA) under the auspices of the American
National Standards Institute (ANSI). The code is revised every three years.
Several organizations, including the UL, have established standards for flame and
smoke that apply to network cables laid inside buildings. However, the NEC contains

the standards most widely supported by local licensing and inspection officials.
NOTE
For more informa-
tion on the Under-
writers Laboratories,
Inc., visit www.ul.com.
NOTE
For more informa-
tion on the National
Fire Protection Asso-
ciation (NFPA), visit
www.nfpa.org/Home/
index.asp.
appen_a.fm Page 905 Tuesday, May 20, 2003 4:54 PM
906 Appendix A: Structured Cabling
NEC Type Codes
NEC type codes are listed in catalogs of cables and supplies. These codes classify spe-
cific categories of products for specific uses, as shown in Table A-1.
Generally, interior network cables are listed in the category of type CM for communi-
cations or type MP for multipurpose. Some companies choose to run their cables through
the testing process as remote-control or power-limited circuit cables CL2 or CL3
(Class 2 or Class 3) general tests instead of through the CM or CP tests, but the flame
and smoke criteria is generally the same for all tests. The differences between these
markings concern the amount of electrical power that could run through the cable in
the worst case. MP cable is subjected to tests that assume the most power-handling
capability, with CM, CL3, and CL2 going through tests with decreasing levels of
power handling.
Safety Around Electricity
In addition to learning about the industry’s safety organizations, the cable installer
should learn about basic safety principles that will be used every day on the job and

that are also necessary for the curriculum labs. Because many hazards exist when
installing cable, the installer should be prepared for all situations so that accidents or
injuries can be prevented.
Table A-1 NEC Cable Type Codes
Type of Cable Description
OFC (fiber optic) Contains metal conductors inserted for strength.
OFN (fiber optic) Contains no metal.
CMP (communication plenum) Passed tests showing limited spread of flame and
low smoke. Plenum cable typically is coated with
a special jacket material such as Teflon. The letter
P in this code defines a plenum as a channel or
ductwork fabricated for handling air.
CMR (communications riser) The letter R shows that the cable has passed simi-
lar but slightly different tests for the spread of
flame and production of smoke, compared to CMP
cable. For example, riser cable is tested for its
burning properties in a vertical position. Accord-
ing to the code, you must use cable rated for riser
service when the cable penetrates a floor and a
ceiling. Riser cables typically have a polyvinyl
chloride (PVC) outer jacket.
appen_a.fm Page 906 Tuesday, May 20, 2003 4:54 PM
Safety 907
High Voltage
Cable installers work with wiring designed for low-voltage systems. The voltage applied
to a data cable would be hardly noticeable to most people. However, the voltage of
network devices that data cables plug into can range from 100V to 240V (in North
America). If a circuit failure allowed the voltage to become accessible, it could give the
installer a dangerous shock—and it could be fatal. In addition, it is not unheard of for
a low-voltage installer inadvertently to skin the insulation off existing high-voltage

wiring and contact voltage that way.
Do not become complacent about the hazards of high-voltage wiring nearby just because
most of the work deals with low-voltage. If someone suddenly comes in contact with
high voltage, that person might find it difficult to control his or her muscles or might
not have the ability to pull away.
Lightning and High-Voltage Danger
High voltage is not limited to power lines; lightning is another source of high voltage.
Because lightning can be fatal and also can damage network equipment, care must be
taken to prevent it from entering the network cabling.
The following precautions should be taken to avoid personal injury and damage to
network equipment from lightning and electrical shorts:
■ All outside wiring must be equipped with properly grounded and registered
signal circuit protectors at the point that they enter the building, known as the
entrance point. These protectors must be installed in compliance with local tele-
phone company requirements and applicable codes. Telephone wire pairs should
not be used without authorization. If authorization is obtained, do not remove or
modify telephone circuit protectors or grounding wires.
■ Never run wiring between structures without proper protection. In fact, protection
from lighting effects is probably one of the biggest advantages to using fiber-optics
between buildings.
■ Avoid wiring in or near damp locations.
■ Never install or connect copper wiring during electrical storms. Improperly pro-
tected copper wiring can carry a fatal lightning surge for many miles.
High-Voltage Safety Test
Voltage is invisible. Its effects are seen in tools that run, equipment that operates, or
the unpleasant experience of getting shocked.
appen_a.fm Page 907 Tuesday, May 20, 2003 4:54 PM
908 Appendix A: Structured Cabling
When working with anything that plugs into the wall for power, it is a safety best prac-
tice to check for voltages on surfaces and devices before coming in contact with them.

Using a known reliable voltage-measurement device such as a multimeter or voltage
detector, take measurements immediately before starting work. Measure again whenever
work is resumed the following day or after a break on any job; someone might have
made changes. Recheck the measurements again when finished.
Some forms of electricity cannot be predicted. Lightning and static electricity fall into
this category. Never install or connect copper wiring during electrical storms; copper
wiring can carry a fatal lightning surge for many miles. This is particularly an issue
with external wiring that is strung between buildings or underground wiring. Equip all
outside wiring with properly grounded and approved signal circuit protectors. These
protectors must be installed in compliance with the local codes, which, in most cases,
align with national codes.
Grounding
Grounding works by providing a direct path to the earth for any voltages that come in
contact with it. Equipment designers purposely isolate the circuits in equipment from
the chassis—that is, the box where the circuits are mounted. Any voltage that leaks
from the equipment to its chassis should not stay in the chassis. Grounding equipment
conducts any stray voltage to the earth without hurting that equipment. Without a
proper path to the ground, stray voltages use another path to the ground, such as a
person’s body.
The grounding electrode is the metal rod that is buried in the ground near the entrance
point of the building—that is, the place where electricity enters a building. How the
ground system connects to the earth is often another matter. For years, cold-water
pipes, which enter the building from the underground water mains, were considered
good grounds. Large structural members, such as I-beams and girders, were also
acceptable. Although these might provide an adequate path to the ground, most local
codes now require a dedicated grounding system, such as installed grounding conduc-
tors connecting equipment to grounding electrodes.
Be aware of the grounding system in the lab and on each job site. Verify that the ground-
ing system actually works. It is not uncommon to find that grounding was improperly
done or never was installed in the first place. A more common situation occurs when

an installer takes a few shortcuts and accomplishes a technically adequate ground, but
in a nonstandard way. Later, changes to other parts of the network or to the building
itself might destroy or eliminate the nonstandard ground system, leaving equipment
and people at risk.
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