Codes, Standards, and Safety Practices

Codes, Standards, andSafety Practices

In this chapter, you will learn about the following

To protect a home from fire or other dangers related to its electrical and structured wiring, a variety of product, installation, and safety standards, guidelines, and practices are published by a number of trade, industry, and specialty organizations and associations. Many of these standards have been incorporated into local building codes, so they aren’t something that can be ignored.

In this chapter, I discuss the standards that impact the design and installation of structured wiring systems, including audio, speaker, video, and control wiring, as well as the safety practices that should be followed on a job site.

Residential Standards Organizations

The materials and practices used when installing structured wiring in a residential setting are developed by a group of industry, governmental, and trade organizations. The standards produced by these organizations are adopted to ensure the success and performance of electrical and communication systems and the safety of the technicians and the residents and occupants of buildings.

In this chapter, we first look at the organizations publishing residential system standards and then at the standards that govern the materials and practices that should be used when installing structured wiring and devices in a house. The organizations that develop and publish standards that cover the specification and installation of residential system wiring are

American National Standards Institute (ANSI)

ANSI, pronounced “ann-see,” is an agency of the United States federal government that is charged with the responsibility of developing and approving standards that cover a variety of technology, including computers and data communications, and weights and measurements. ANSI is the U.S. representative to the International Organization for Standardization (ISO) that is the worldwide standards authority.

ANSI works with several other agencies to develop and publish (for a fee) its standards, including the Electronic Industries Alliance (EIA) and the Telecommunication Industry Association (TIA), and often publishes standards in conjunction with these independent trade organizations. Examples of jointly issued standards are the ANSI/TIA/EIA 568, 569, and 570 wire and cabling standards.

Electronic Industries Alliance (EIA)

EIA (“ee-eye-aa”) is an alliance of trade and industry associations that work together to sponsor and promote data communication standards. The member associations of the EIA are

Most of the EIA standards that apply to residential wiring are issued jointly with ANSI and TIA, including the ANSI/EIA/TIA 568 and 570 standards.

Institute of Electrical and Electronic Engineers (IEEE)

The IEEE (“eye-triple-ee”) is a worldwide, technical, professional association of engineers that is a leading standards authority in a variety of technical areas that includes aerospace, biomedical, computer, electrical power, telecommunications, and consumer electronics engineering, and more. The IEEE has over 900 published standards with several hundred more in development.

The IEEE standards that most impact residential systems are its 802 computer networking standards. The number 802 refers to February 1980, which is when the committees working on networking standards were first organized. The IEEE 802 committees are numbered to differentiate their responsibilities and the standards each committee develops. Table 4-1 lists the committees of the IEEE 802 project and the networking specification associated with home networking each is charged with defining.

Table 4-1: The IEEE 802 Project Committees

IEEE 802 Committee

Responsibility

802.1

Overall specification for a local area network (LAN) and LAN connectivity.

802.2

Logical Link Control (LLC) standards that define the transmission of data from one device to another.

802.3

Media Access Control (MAC) standards that define the control of access to a network – commonly referred to as the Ethernet standards.

802.7

Defines broadband LANs, common to home networks.

802.9

Defines the integration of voice and digital data on a network.

802.10

Defines the standards for security between networked devices.

802.11

Defines the standards for wireless infrared (IR) or radio frequency (RF) networks.

802.15

Defines personal area networks (PANs)

International Organization for Standardization (ISO)

The ISO (“eye-ess-oh”) is an international, non-treaty organization of voluntary members that develops and maintains a variety of technology standards, including standards governing computers, networking, and communications. In fact, the ISO’s Open System Interconnect Reference Model (the OSI model for short) is the globally accepted international networking standard model. The ISO is organized as a working network of the national standards authorities of 147 countries, including ANSI from the U.S.

An emerging standard of ISO is the residential gateway, which defines a network interface device that provides service access to a home for such services as telephone, cable television, and Internet access. The ISO standard defines a residential gateway (RG) as the physical devise that terminates all external access networks to a home and also serves to terminate all internal networks as well. The ISO’s RG Group sees a residential gateway as a single device that consolidates, coordinates, and integrates communication signals from both internal and external networks. The development of the RG standard by ISO and the International Electrotechnical Commission (IEC) is in conjunction with the proposed Home Electronic System (HES), also called HomeGate, now under development. The IEC is an international organization that publishes electrical and electronic compatibility, design, and safety standards.

National Fire Protection Association (NFPA)

The NFPA is an international association with well over 75,000 members representing more than 80 national trade and professional organizations that are focused on the development and publishing of fire safety codes, standards, and research to minimize the possibilities and impact of fire and other safety risks. In terms of home automation projects and structured wiring, the NFPA’s most important standard is the National Electrical Code (NEC), which was last published in 2002 and is scheduled for revision in 2005.

The NEC (also known as NFPA 70) is the most widely adopted building code component in the world, including the United States, for electrical installations. The NEC covers the installation of electrical conductors, including the wiring used in structured residential wiring systems.

Telecommunications Industry Association (TIA)

TIA is a trade organization of telecommunication product and service providers that among other industry activities, develops and publishes a variety of wire and media specifications and testing standards, including those for commercial and residential applications.

TIA is organized into five product-specific divisions: User Premises Equipment, Network Equipment, Wireless Communications, Fiber Optics, and Satellite Communications. The primary TIA standards that apply in home networking situations are those that govern Cat 5 wiring connections and testing, which are TIA/EIA 568 and 570.

Federal Communications Commission

The U.S. Federal Communications Commission (FCC) oversees the telecommunications industry through the issuance of regulations and operating rules. Two FCC rules apply to the installation of a home communication system:

Underwriters Laboratories (UL)

Perhaps the best known for product testing, UL is an independent, nonprofit product safety testing organization. Most cable and wire manufacturers voluntarily submit their products to UL for fire and electrical safety testing against the NEC and other NFPA standards.

Primarily, the testing performed by UL on cable and wiring is for compliance with Articles 725, 760, 800, and 820 of the NEC, which define the standards for communications, fire protection, and cable television wiring, respectively. A cable or other electric or electronic device bearing the UL logo is certified to meet the requirements of the applicable standards.

UL issues a variety of certification labels to certify conformance of wiring and electrical products to a variety of national and proprietary standards, including:

The UL also issues Canadian versions of these certifications that are based on the Canadian Standards Authority (CSA) using the C-UL recognized component mark. The CSA is a nonprofit, independent testing laboratory that performs essentially the same services in Canada as the UL provides in the U.S. An important wire and cable certification issued by the CSA is the vertical flame testing (FT1/FT4) certification that specifies the flame resistance of wire and cable. Conforming products are marked with the symbol shown in Figure 4-3.

Figure 4-3: The CSA certified product mark

Another standards testing certification is the Conformity to European Directive (CE) that covers virtually all of the same standards used by UL and CSA for products sold in the European Economic Community (EEC). Figure 4-4 shows the mark carried by CE certified products.

Figure 4-4: The CE certified product mark

Residential Systems Standards

There are several construction, safety practices, materials, and wiring standards that govern how a house is built, including wiring the house for electrical and communications systems. The primary standards a home technology technician should be familiar with are

ANSI TIA EIA Standards

The standards that are jointly sponsored by ANSI, the TIA, and the EIA cover a variety of cabling and cable installation requirements. However, the specific standards that come into play in home systems are those dealing with data, audio, video, and other cabling and termination, particularly ANSI/TIA/EIA 568a and 568b and ANSI/TIA/EIA 570.

ANSI/TIA/EIA 568

The 568 standard is the Commercial Building Telecommunications Cabling Standard. Although this standard was initially developed for commercial building telephone and data cabling systems, it is also the accepted standard for data cabling in a home setting as well.

The purpose of these standards is to provide the specification for generic telecommunication cabling and to assist technicians with the planning and installation of telecommunication cable. These standards also prescribe the performance testing criteria for standard system configurations and their components. Specifically, the 568 standards specify the component elements used in designing and installing the following home cabling types:

UTP Cabling Systems

The 568 standards also specify the UTP cabling categories that are acceptable for use as horizontal cabling and patch cords. Table 4-2 lists the characteristics for the UTP cabling that is acceptable for use as horizontal cabling.

Table 4-2: ANSI/TIA/EIA UTP Cabling Standards

Category

Bandwidth

Wire Pairs

Maximum Segment Length

LAN Applications

Cat3

16 MHz

2

100 meters

10BaseT, 4 Mbps

Cat4

20 MHz

2

100 meters

16 Mbps, Token Ring

Cat5

100 MHz

4

100 meters

100BaseT, ATM, CDDI

Cat5e

100 MHz

4

100 meters

1000BaseT

Cat 5 wire is the most commonly used cabling on Ethernet and Token Ring networks. However, while Cat 5 wiring is required for 100 Mbps networks, how the cable is installed can have a huge impact on whether or not the cable will actually support that much bandwidth.

Three specific and very important guidelines are as follows:

568a and 568b Standards

Within the 568 standard are two separate cable termination standards for UPT cabling: 568a and 568b. Each of the termination standards prescribes the wires in a UTP cable that are to be connected to specific pins on an RJ-45 connector. Which of the two termination standards are used depends on the intended use of the cable. The basic difference between these standards is that the 568a specification can be used for both voice and data transmission and 568b is more suitable for data transmission only.

Tables 4-3 and 4-4 show the RJ-45 plug pin and wire match-ups for 568a and 568b, respectively.

Table 4-3: The EIA/TIA 568a Cable Termination

End 1 Pin

Wire

End 2 Pin

1

White green

1

2

Green

2

3

White orange

3

4

Blue

4

5

White blue

5

6

Orange

6

7

White brown

7

8

Brown

8

Table 4-4: The 568b pinouts for the RJ-45 connectors on a Cat 5 UTP cable

End 1 Pin

Wire

End 2 Pin

1

White orange

1

2

Orange

2

3

White green

3

4

Blue

4

5

White blue

5

6

Green

6

7

White brown

7

8

Brown

8

The 568 standards also specify IDC (Insulation Displacement Connector) connectors at the distribution or telecommunications center and an 8-position modular jack in the work area (rooms of the house), which means an RJ-45 connector. These standards also specify two distinct wire/connector pinouts, which are identified as 568a and 568b. The primary difference between the two is that 568a supports telecommunications (meaning voice telephone signals) and 568b doesn’t. Figures 4-5 and 4-6 show the pin/wire pattern (pinout) for these two standards.

Figure 4-5: The pinout (wire and connector pin pattern) defined by ANSI/EIA/TIA 568a for UTP cabling

Figure 4-6: The pinout defined by ANSI/EIA/TIA 568b for UTP cabling

ANSI TIA EIA 569

The 569 standard deals with telecommunications design and installation of devices used inside and between buildings and for rooms or work areas where cable media and equipment are installed. This standard applies to home networking situations where a central distribution facility is installed and defines the construction and termination method used for horizontal cabling connected into distribution panels.

TIA EIA 570A

The 570 standard defines the basic requirements for residential structured wiring. This standard was developed by a panel of cabling experts that included cable professionals, telephone companies, cable system manufacturers, and the like. It is the nationally accepted standard covering the design and installation of low voltage wiring in residential dwellings.

However, the primary achievement of the 570 standard is that it consolidates the specifications, installation practices, and performance criteria for the media used in audio, control, data, and video systems into a single conformance standard.

The 570 standard defines the following specifications:

One of the specific areas of specification in the 570 standard is in communication outlets. The 570 standard defines two standard grades for communication outlets:

IEEE Ethernet Cable Standards

The IEEE 802 standards designate cabling standards for use on an Ethernet network with a special coding scheme that generally describes a cable’s characteristics. The most common of the Ethernet cable specifications are listed in Table 4-5.

Table 4-5: The IEEE 802 Ethernet Cable Standards

Ethernet Cable Standard

Cable Defined by Standard

Minimum Cable Type

10Base2

10 Mbps thin coaxial network cable

50-ohm RG-58 coaxial cable

10BaseT

10 Mbps unshielded twisted-pair network cable

Cat 3 unshielded twisted pair (UTP)

100BaseT

100 Mbps unshielded twisted-pair network cable

Cat 5 UTP

100BaseF

100 Mbps fiber optic network cable

Single-mode optical fiber

1000BaseT

1Gbps copper cable

Cat 5e UTP

1000BaseF

1Gbps fiber optic cable

Multimode optical fiber

The coding scheme shown in Table 4-5 has three parts to it: a number (10/100/1000), the word “Base,” and a number or letter indicating the media type (2, T, F, and X). For example, 10BaseT, 100BaseT, and 1000BaseT all specify cables that carry 10 Mbps, 100 Mbps, and 1 Gbps (1,000 Mbps) of bandwidth, respectively.

The word “Base” indicates that baseband signaling is used to transmit the data, as opposed to narrowband or broadband. Baseband is a network technology that sends its data over a single carrier frequency. Baseband networks require all nodes to participate in every message sent over the network.

The final part to the cable specification designator is one or two characters that indicate a variety of information, depending on the cable and its speed. In the case of 10Base2, the “2” indicates a maximum segment length of approximately 200 meters (actually it’s 185 meters). Cables may also have a T or an F, which refer to twisted-pair wire and fiber optic cable, respectively.

The IEEE 802 specification includes standards for wireless networking media as well. The primary two standards in the IEEE 802 are 802.11, which deals with wireless Ethernet, and 802.15, which deals with wireless personal area networking (PAN). I discuss the wireless media standards later in the chapter.

National Electric Code (NEC)

The National Electric Code, or NEC, is a trademarked standard. It is also known as NFPA 70 and is published by the National Fire Protection Association (NFPA) as a guideline to avoid and prevent electrical shock and fire hazards from residential wiring systems. The NEC is published periodically and the current (at the time of this writing) version of the standard is 2002, with the next updated version due in 2005.

There is essentially an NEC standard for every electrical circuit in a home. Most of the NEC standards cover electrical power circuits, but there are also sections that govern communications media and the transmission of electrical signals over that media. To give you an idea of the extensiveness of the NEC standards, we have listed a sampling of the NEC standards that could impact a structured wiring system in Table 4-6.

Table 4-6: A Sampling of NEC Standards Sections and the Electrical Area Defined

NEC Section

Applies To

250-104

Using water pipes as grounding conductors

300-4

Size of bored holes in joists, rafters, or wall studs

300-15

Wire splices

300-22

Type NM cable used in HVAC cold air returns

336-18

Non-metallic cable (Type NM)

370-16

Outlet box volume and size

370-23

Electrical boxes

370-25

Outlet box covers

410-8

Lighting fixtures in clothes closets

Job Safety Regulations

Virtually every industrialized country in the world has a governmental agency that creates, publishes, and administers job safety and health codes and regulations. In the United States, the agency is the Occupational Safety and Health Administration (OSHA) of the U.S. Department of Labor. In Canada, the Human Resources Development Canada (HRDC) has this responsibility; in England, the government’s Health and Safety Executive (HSE) oversees job safety; and in Japan, the Japan Occupational Safety and Health Office (JOSHO) administers worker safety issues.

Working in an alliance with the National Home Builders Association (NHBA), OSHA has developed and published a Code for Federal Regulations (CFR) specifically addressing job safety issues for construction trades, entitled “Selected Construction Regulations (SCOR) for the Home Building Industry (29 CFR 1926).” Table 4-7 lists a few of the section titles included in this section of the OSHA codes.

Table 4-7: A sampling of the coverage included in the SCOR published by OSHA for the home building trades

Section

Topic

1926.20

General safety and health provisions

1926.23

First aid and medical attention

1926.24

Fire protection and prevention

1926.28

Personal protective equipment

1926.55

Gases, vapors, fumes, dusts, and mists

1926.102

Eye and face protection

1926.302

Power-operated hand tools

1926.400

Electrical – General

1926.404

Wiring design and protection

1926.405

Wiring methods, components, and equipment for general use

1926.417

Lockout and tagging of circuits

OSHA and NHBA Job Safety Standards

The National Homebuilders Association (NHBA) in conjunction with OSHA publishes the Jobsite Safety Handbook, something that all home automation professionals should be very familiar with. In fact, if you are considering CEDIA certification, it is a must-read before taking the exams.

The portion of the handbook that relates directly to the work of a home technology integration or home automation professional is the “Electrical” section, which includes safety guidelines that cover how to work with electrical and electronic systems safely. The safety guidelines cover the following:

Building Codes

In the not-so-distant past, many countries had their own version of a national or uniform building code aimed at protecting the health, safety, and welfare of the public, which means homeowners or occupants. Prior to 1999, the International Conference of Building Officials (ICBO) published the Uniform Building Code (UBC). However, in 2000, the ICBO joined with the International Codes Council to publish a single guideline called the International Building Code (IBC).

The intent of the IBC is to ensure that a building’s occupants are protected from fire and structural collapse by developing construction material and practice guidelines that provide for proper design, construction, and code compliance. Another important part of the IBC is to provide uniformity in the construction industry worldwide, including consistent minimum quality, durability, and safety in constructed buildings.

Local Building Codes and Standards

Each state, province, county, parish, shire, city, town, and township can, and most do, develop local building codes that incorporate or extend the national and international building, product, and safety codes and regulations.

For example, in its “Computing and Telecommunications Architecture Standards for Building Wiring,” the State of Washington includes the standards listed in Table 4-8, among others, as the basis for its regulations.

Table 4-8: Example of the Individual Standards included in the State of Washington’s Computing and Telecommunications Wiring Standard

Wiring Standard

Description

TIA/EIA-568A

Commercial Building Telecommunications Wiring Standard

TIA/EIA-569A

Commercial Building Standard for Telecommunications Pathways and Services

TIA/EIA-570A

Residential and Light Commercial Telecommunications Wiring Standard

TIA/EIA 594

Private Digital Network Synchronization

TIA/EIA 596

Network Channel Terminating Equipment for Switched Digital Devices

TIA/EIA-606

Administration Standard for Telecommunications Infrastructure of Commercial Buildings

TIA/EIA TSB 67

Transmission Performance Specifications for Testing UTP Cabling Systems

TIA/EIA TSB 75

Additional Horizontal Cabling Practices Open Offices

TIA/EIA TSB 95

Additional Transmission Performance Guidelines for 4-pair 100 Ohm Category 5 Cabling

Powerline Standards

The term “powerline” is used frequently to describe the electric lines inside the walls of a home. Technically, “powerline” refers to the system used by most electric utility companies to transmit information across their electrical power grid using narrowband communications. The powerline technology is now available for use with home networks to transmit data across the existing electrical wiring.

When you think about it, powerline technology makes a lot of sense. If you are introducing a network into a home, there are already more electrical outlets installed than the number of Ethernet jacks you’d need to install. Powerline technology is a very low-cost alternative to wiring a home with Cat 5 wiring.

There are three primary standards for powerline technology:

Phoneline Standards

In a similar manner to the way that powerline technologies use the existing electrical lines in a home to transmit data, phone line communications technologies use the existing telephone wiring in the walls of a home to communicate.

The leading technology of phone line communications is the standard developed by the Home PhoneLine Networking Association (HPNA). Many vendors, including several also supporting powerline communications, are supporting this standard as well. HPNA currently operates at 10 Mbps and can coexist with DSL systems that may also be on the phone lines.

Wireless Media Standards

Another network media choice available is wireless networking and it eliminates the concern for wiring altogether. However, there are pros and cons for each media so each should be carefully considered before choosing it as a networking solution. The primary wireless media standards are as follows:

Other Standards

In the preceding sections, I discussed the primary standards that cover the design, installation, termination, and testing for the media included in a home’s structured wiring. However, there are several other standards that apply to the applications and technologies implemented across the wiring. Table 4-9 lists a sampling of other standards and standards organizations that could apply to a whole-house networking implementation, depending on the applications it supports.

Table 4-9: Other Residential Network Technology Standards

Organization

Standard

Description

EIA

EIA-600

CEBus powerline networking

CIC

HomePnP

Home Plug-and-Play

Cable Labs

DOCSIS

Data Over Cable Service Interface Specification

TIA

TR41.5

Residential Gateway

IEEE

IEEE 1394

Standard version of high-speed interface, implemented by Apple Computer as FireWire

VESA

VESA Home Network

High-speed whole-house baseband networking using IEEE 1394

HAVi Consortium

Home Audio Video interface

Digital AV networking interface standard

HomeAPI Working Group

HomeAPI

Programming routines for residential control systems

Review

The organizations that develop and publish the primary standards covering the specification and installation of residential system wiring are: ANSI, EIA, IEEE, ISO, NFPA, TIA, UL, and OSHA.

ANSI is an agency of the United States federal government that is charged with the responsibility of developing and approving standards that cover a variety of technology, including computers and data communications, and weights and measurements. ANSI works with other agencies to develop and publish standards. Examples of jointly issued standards are the ANSI/TIA/EIA 568, 569, and 570 wire and cabling standards.

EIA is an alliance of trade and industry associations that work together to sponsor and promote data communication standards. Most of the EIA standards that apply to residential wiring are issued jointly with ANSI and TIA, including the ANSI/EIA/TIA 568 and 570 standards.

The IEEE is a worldwide, technical, professional association of engineers that is a leading standards authority in a variety of technical areas. The IEEE standards include the 802 computer networking standards.

The ISO is an international, non-treaty organization of voluntary members that develops and maintains a variety of technology standards, including standards governing computers, networking, and communications. An emerging standard of ISO is the residential gateway, which defines a network interface device that provides service access to a home for such services as telephone, cable television, and Internet access.

The NFPA is an international association focused on the development and publishing of fire safety codes, standards, and research to minimize the possibilities and impact of fire and other safety risks. The NFPA publishes the National Electrical Code (NEC), which includes coverage for the installation of electrical conductors, including the wiring used in structured residential wiring systems.

TIA is a trade organization of telecommunication product and service providers that develops and publishes a variety of wire and media specifications and testing standards for residential applications. The TIA/EIA 568 and 570 standards govern Cat 5 wiring connections and testing for home networking installations.

UL is an independent, nonprofit product safety testing organization that tests cable and wire products for fire and electrical safety testing against the NEC and other NFPA standards.

The primary home technology standards are ANSI/EIA/TIA wiring standards, IEEE Ethernet wire standards, the NEC, the OSHA job safety practices, and the International Building Code (IBC).

The ANSI/EIA/TIA 568 standard provides specification for generic telecommunication cabling that prescribe the performance testing criteria for standard system configurations and their components. The 568 standards specify horizontal cable, work area or room cabling, and central distribution termination. The 568 standards also specify the UTP cabling categories for use as horizontal cabling and patch cords.

The 568 standard defines two separate cable termination standards for UPT cabling: 568a and 568b. The 568 standards also specify IDC (Insulation Displacement Connector) connectors at the distribution or telecommunications center and the use of the RJ-45 connector.

The EIA/TIA 570 standard defines the basic requirements for residential structured wiring and is the nationally accepted standard covering the design and installation of low voltage wiring in residential dwellings.

The IEEE 802 standards designate network media standards for use on an Ethernet network with a special coding scheme that generally describes a media’s characteristics. The National Fire Protection Association (NFPA) publishes the National Electric Code (NEC) as a guideline to avoid and prevent electrical shock and fire hazards from residential wiring systems.

Each country has a governmental agency that publishes job safety and health codes and regulations. In the United States, it’s the Occupational Safety and Health Administration (OSHA); in Canada, it’s the Human Resources Development Canada (HRDC); in England, it’s the Health and Safety Executive (HSE); and in Japan, it’s the Japan Occupational Safety and Health Office (JOSHO). OSHA publishes the “Selected Construction Regulations (SCOR) for the Home Building Industry (29 CFR 1926).”

The term “powerline” describes the use of the electrical lines inside a home’s walls to transmit information. The three primary standards for powerline technology are CEBus, HomePlug, and X-10. Phoneline communications technologies use the existing telephone wiring or coaxial cable in the walls of a home to communicate. The leading phoneline standard is the Home PhoneLine Networking Association (HPNA) standard. The primary wireless media standards are IEEE 802.11a, IEEE 802.11b, Bluetooth, and HomeRF.

Questions

  1. Which of the following is not a standards organization listed in this chapter?

    1. ANSI
    2. EIA
    3. NEA
    4. NFPA

  2. Which of the IEEE 802 standards is considered to be the Ethernet standard?

    1. IEEE 802.1
    2. IEEE 802.3
    3. IEEE 802.5
    4. IEEE 802.15

  3. What organization publishes the NEC?

    1. ANSI
    2. ICC
    3. EIA
    4. NFPA

  4. What is the EIA/TIA standard that governs Cat 5 wiring connections?

    1. 232
    2. 402
    3. 568
    4. 570

  5. Which of the UTP cable categories is recommended as 100BaseT media?

    1. Cat 2
    2. Cat 3
    3. Cat 4
    4. Cat 5

  6. Which of the following lists the 568b pinout sequence of the wire colors from Pin 1 to 8?

    1. White green, green, white orange, blue, white blue, orange, white brown, brown
    2. White green, blue, white blue, green, white orange, orange, white brown, brown
    3. White orange, orange, white green, blue, white blue, green, white brown, brown
    4. White green, blue, white blue, green, white brown, brown, white orange, orange

  7. What is the TIA/EIA standard that specifies residential structured wiring?

    1. 568a
    2. 568b
    3. 570
    4. 802

  8. In the term 10BaseT, what does the “Base” refer to?

    1. Broadband
    2. Baseband
    3. Narrowband
    4. Base rate interface

  9. Which of the IEEE 802 network standards defines wireless Ethernet standards?

    1. 802.3
    2. 802.10
    3. 802.11
    4. 802.15

  10. What government agency publishes the “Selected Construction Regulations (SCOR) for the Home Building Industry (29 CFR 1926)”?

    1. Occupational Safety and Health Administration (OSHA)
    2. Department of Agriculture
    3. Housing and Urban Development (HUD)
    4. American National Standards Institute (ANSI)

Answers

  1. D. The National Education Association doesn’t publish home wiring system standards.
  2. B. The other standards listed are for LAN connectivity, Token Ring networks, and personal area networks, respectively.
  3. D. The National Fire Protection Association publishes the NEC approximately every 3-4 years.
  4. C. Actually there are two standards, the 568a and the 568b.
  5. D. Cat 2 isn’t used for networking. Cat 3 and Cat 4 are recommended for 10BaseT and Token Ring networks.
  6. C. The difference between the 568a and 568b is the placement of only one pair.
  7. C. The 568 standards deal with UTP cable and its termination, and the 802 standards are published by IEEE.
  8. B. Baseband refers to the fact that the cable media is able to carry only a single signal.
  9. C. The other 802 standards deal with Ethernet media access, metropolitan area networking (MAN), and personal area networking (PAN), respectively.
  10. A. This agency is charged with issuing worker and workplace safety standards and practices.

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