Chapter 3 - Telecommunications Spaces

Question 1

Augmented Class F balanced twisted-pair has performance characteristics specified up to _____ MHz

a. 500
b. 600
c. 1000
d. 2000

Answer 1

c. 1000

Question 2

EPONs, dispersion unshifted fiber

a. G.652
b. G.653
c. G.655
d. G.656
e. G.657

Answer 2

a. G.652

p 4-20 Table 4.2

Supports 1 Gigabit Ethernet, 10 Gigabit Ethernet and SONET.

Question 3

EPONs, dispersion shifted fiber

a. G.652
b. G.653
c. G.655
d. G.656
e. G.657

Answer 3

b. G.653

p 4-20 Table 4.2

Supports STM-64 and SDH systems with an unequal channel spacing in the 1550 nm wavelength region

Question 4

EPONs, non-zero dispersion shifted fiber

a. G.652
b. G.653
c. G.655
d. G.656
e. G.657

Answer 4

c. G.655

p 4-20 Table 4.2

Primarily utilized in submarine and long-haul terrestrial applications.

Question 5

EPONs, wideband non-zero dispersion shifted fiber

a. G.652
b. G.653
c. G.655
d. G.656
e. G.657

Answer 5

d. G.656

p 4-21 Table 4.2

Used in within a pair of bounding both CWDM and DWDM systems.

Question 6

EPONs, bending loss insensitive fiber.

a. G.652
b. G.653
c. G.655
d. G.656
e. G.657

Answer 6

e. G.657

p 4-21 Table 4.2

Supports small volume fiber management systems and low radius mounting.

Question 7

Within backbone applications, a PON is typically a point-to-multipoint, fiber to the premises network architecture, in which unpowered optical splitters are used to enable a single fiber to serve multiple premises, typically ___ to ___

a. 12, 48
b. 32, 128
c. 64, 128
d. 128, 256

Answer 7

b. 32, 128

p 4-18

A PON configuration reduces the amount of optical fiber and CO equipment required, compared with PTP architectures.

Question 8

The aggregation device, called the OLT, supports a minimum of ___ subscribers per port by means of a passive optical splitter.

a. 12
b. 14
c. 16
d. 20

Answer 8

c. 16

p 4-18

The EFM objective to support EPONs is based on a number of economic advantages. The aggregation device, called the OLT, supports a minimum of 16 subscribers per port by means of a passive optical splitter.

Question 9

In a multiple hierarchical level campus backbone design, one or more _____ serve more than one building.

a. Intermediate cross-connects
b. Main cross-connects
c. Campus distributors
d. Horizontal cross-connects

Answer 9

a. Intermediate cross-connects

p 4-25

Larger campus cabling systems may require multiple hierarchical levels. This design provides a campus backbone that uses selected ICs (BDs) to serve a number of buildings (e.g., the science buildings in Figure 4.16) rather than linking all the buildings directly to the MC (CD). The ICs (BDs) are then linked to the MC (CD).

Question 10

When designing an in-building backbone distribution system using slots, the slot area sizing should be increased by _____ with each 3716 m2 (40,000 ft 2) increase in useable floor space served.

a. 0.008 m2 (12 in2)
b. 0.016 m2 (24 in2)

Answer 10

a. 0.008 m2 (12 in2)

p 4-46

The size of the pathway using slots should be one slot sized at ≈0.04 m2 (60 in2) for up to ≈3716 m2 (40,000 ft2) of usable floor space served by that backbone distribution system. The slot area should be increased by ≈0.008 m2 (12 in2) with each ≈3716 m2 (40,000 ft2) increase in usable floor space served by that backbone.

Question 11

When planning space for terminations, the ITS designer should plan for a clear space of ___ inches above and below the connecting hardware for cable handling.

a. 5
b. 6
c. 8
d. 12

Answer 11

a. 5

p 3-14

The ICT distribution designer should plan for:
• A minimum clear space of ≈127 mm (5 in) above and below the top and bottom of the connecting hardware for cable management.

• Additional rack, cabinet, enclosure, or backboard space for routing cables, patch cords, equipment cords, or cross-connect jumpers (cables may also be routed behind the connecting hardware).

Question 12

When designing the layout of a telecommunications room, if an entrance facility is housed at the same location, then the designer should:

a. Include space for cabling protection, grounding (earthing), enclosures, and splice cases
b. Allow additional space for cross-connect components
c. Include space for splicing and ladder racking
d. Provide clear separation and identification of each tenant’s equipment and terminations

Answer 12

a. Include space for cabling protection, grounding (earthing), enclosures, and splice cases

p 3-22 Table 3.4

Question 13

The placement of cross-connect fields, patch panels, and active equipment in the horizontal cross-connect (floor distributor) should allow for the total length of patch cords, equipment cords, or jumpers plus the work area equipment cord to not exceed ___ per channel.

a. 5 m (16.5 ft)
b. 10 m (33 ft)
c. 15 m (49.5 ft)
d. 20 m (66 ft)

Answer 13

b. 10 m (33 ft)

p 3-14

≈10 m (33 ft) total for patch cords/jumpers, equipment cords connected to the HC (FD), plus the work area equipment cord.

≈5 m (16.5 ft) for patch cords, equipment cords, or jumpers in the HC (FD).

≈20 m (66 ft) for patch cords or jumpers that serve MC (CD) or IC (BD).

Question 14

The recommended height for racks, cabinets, or enclosures is:

a. 2.1 m (7 ft)
b. 2.3 m (7.5 ft)
c. 2.4 m (8 ft)
d. 2.6 m (8.5 ft)

Answer 14

a. 2.1 m (7 ft)

p 3-14

Racks, cabinets, or enclosures are recommended to have a height of ≈2.1 m (7 ft) and have a rail size and top flange width of ≈483 mm (19 in) (see Figure 3.1).

Question 15

When planning space for wall terminations, do not mount termination hardware closer than _____ to any corner.

a. 76 mm (3 in)
b. 102 mm (4 in)
c. 127 mm (5 in)
d. 152 mm (6 in)

Answer 15

d. 152 mm (6 in)

p 3-14

To allow access, do not mount termination hardware closer than ≈152 mm (6 in) to any corner.

Question 16

What type of cabling facility is typically housed in a telecommunications enclosure (TE)?

a. Main or zone cross-connect
b. Intermediate or main cross-connect
c. Horizontal cross-connect
d. Horizontal or zone cross-connect

Answer 16

c. Horizontal cross-connect

p 3-19

TEs typically serve a relatively small number of users on a floor, and as such, the type of cabling facility that may be housed in TEs is typically limited to HCs (FDs).

Question 17

When allocating space for cable terminations, up to _____ percent more space may be required for the routing of cables and cords to and from the cross-connect fields.

a. 10
b. 15
c. 20
d. 25

Answer 17

c. 20

p 3-12

These space allocations do not include cable runs to and from the cross-connect fields. Up to 20 percent more space may be required for proper routing of cables, jumpers, equipment cords, and patch cords.

Question 18

The HVAC system serving a telecommunications space should maintain a positive pressure in the space, with a minimum of _____ air change(s) per hour.

a. One
b. Two
c. Three
d. Four

Answer 18

a. One

p 3-6

Maintain a positive pressure with a minimum of one air change per hour in the telecommunications space.

Question 19

On equipment racks using angled patch panels, the use of _____ cable management is recommended.

a. Vertical
b. Horizontal

Answer 19

a. Vertical

p 3-16

When placing equipment rack, a vertical cable management panel should be placed on at least one side of the rack or between the rack and the room wall.

Question 20

The recommended height for racks, cabinets, or enclosures is:

a. 2.1 m (7 ft)
b. 2.3 m (7.5 ft)
c. 2.4 m (8 ft)
d. 2.6 m (8.5 ft)

Answer 20

a. 2.1 m (7 ft)

p 3-14

Racks, cabinets, or enclosures are recommended to have a height of ≈2.1 m (7 ft) and have a rail size and top flange width of ≈483 mm (19 in) (see Figure 3.1).

Question 21

If there are fewer than _____ work areas, the equipment room (ER) shall be no less than 15 m2 (160 ft2) in size.

a. 50
b. 100
c. 150
d. 200

Answer 21

d. 200

p 3-39

If there are fewer than 200 work areas, the ER shall be no less than ≈15 m2 (160 ft2). For special-use buildings (e.g., hospitals, hotels), ER size requirements may vary

Question 22

If there are multiple telecommunications spaces on the same floor, they shall be interconnected with a minimum of _____ conduit(s) (or another type of pathway with equivalent capacity).

a. One 78 mm (3 trade size)
b. Two 78 mm (3 trade size)
c. One 103 mm (4 trade size)
d. Two 103 mm (4 trade size)

Answer 22

d. Two 103 mm (4 trade size)

p 3-4

Multiple telecommunications spaces on the same floor shall be interconnected with a minimum of two ≈103 mm (4 trade size) conduits or a pathway that provides equivalent capacity.

Question 23

If the minimum sizing guidelines for telecommunications spaces cannot be met, a space 2.6 m (8.5 ft) high, 1.83 m (6 ft) wide, and 1.2 m (4 ft) deep should be provided for every _____ 4-pair cable terminations served.

a. 120
b. 240
c. 360
d. 480

Answer 23

b. 240

p 3-11

If, for reasons beyond the control of the ICT distribution designer, the minimum size guidelines cannot be met, ≈1.2 m (4 ft) depth by ≈1.83 m (6 ft) width by ≈2.6 m (8.5 ft) height (inside dimensions) of the telecommunications space should be provided with sliding or double ≈914 mm (36 in) doors for every 240, 4-pair cable terminations served.

Question 24

If a separate access provider (AP) space is required in or adjacent to the entrance facility, a space of at least _____ should be allocated by the designer for each AP.

a. 0.91 m x 1.83 m (3 ft x 6 ft)
b. 0.91 m x 2.1 m (3 ft x 7 ft)
c. 1.2 m x 1.83 m (4 ft x 6 ft)
d. 1.2 m x 2.4 m (4 ft x 8 ft)

Answer 24

c. 1.2 m x 1.83 m (4 ft x 6 ft)

p 3-33

If a separate AP space is required, it should be in or adjacent to the EF and may require a mesh partition or locked cabinet. A space of at least ≈1.2 m by ≈1.83 m (4 ft by 6 ft) should be allocated for each AP (see Figure 3.7).

Question 25

Multiple telecommunications rooms on a floor should be considered if the usable floor space to be served exceeds:

a. 929 m2 (10,000 ft2)
b. 465 m2 (5000 ft2)
c. 697 m2 (7500 ft2)

Answer 25

a. 929 m2 (10,000 ft2)

p 3-21

If the usable floor space to be served exceeds ≈929 m2 (10,000 ft2), consider additional TRs.

Question 26

Trays and conduits located within the ceiling in telecommunications spaces should be above _____ high.

a. 3 m (10 ft)
b. 2.4 m (8 ft)
c. 2.6 m (8.5 ft)
d. 2.74 m (9 ft)

Answer 26

b. 2.4 m (8 ft)

p 3-4

Trays and conduits located within the ceiling should protrude into the room a distance of ≈25.4 mm (1 in) to ≈51 mm (2 in) without a bend and above ≈2.4 m (8 ft) high.

Question 27

Multiple telecommunications rooms are required on a floor if the cable length between the horizontal cross- connect / floor distributor and the telecommunications outlet location, including slack, exceeds:

a. 90 m (295 ft)
b. 100 m (328 ft)

Answer 27

a. 90 m (295 ft)

p 3-21

Multiple rooms are required if the cable length between the HC (FD) and the telecommunications outlet location, including slack, exceeds ≈90 m (295 ft).

Question 28

Telecommunications spaces that are intended to serve multiple tenants in a building should be located in:

a. A common space
b. The largest tenant’s space
c. Each tenant’s space

Answer 28

a. A common space

p 3-1

Telecommunications spaces that are intended to serve multiple tenants should be located in common spaces that should be accessible through a common corridor or outside door.

Question 29

You have determined that the equipment room (ER) you are designing will be the minimum size of 15 sq m (160 sq ft) and is servicing 80 work areas but architectural changes will add 175 work areas, which will require you to add a horizontal cross-connect (HC). What size should the equipment room (ER) be?

a. 18 sq m (191 sq ft)
b. 23 sq m (250 sq ft)
c. 31 sq m (330 sq ft)
d. 37 sq m (400 sq ft)

Answer 29

a. 18 sq m (191 sq ft)

p 3-38

Multiply the number of work areas to be served by ≈0.07 m2 (0.75 ft2) and the number of BAS devices to be served by ≈0.023 m2 (0.25 ft2) to determine the ER size.

Or 80 + 175 = 255 x 0.75 ~ 191 sq. ft.

Question 30

If the usable floor space is unknown, then deduct _____ percent of the total area available to estimate the usable area.

a. Five
b. Ten
c. Fifteen
d. Twenty

Answer 30

d. Twenty

p 3-38

If the usable floor space is unknown, deduct 20 percent of the total floor area to estimate the usable floor space

Question 31

In addition to voice and data services, an equipment room (ER) can be designed to include all of the following EXCEPT:

a. CATV and CCTV facilities
b. Life safety facilities
c. Building electrical service monitoring and controls
d. Audio and paging equipment

Answer 31

c. Building electrical service monitoring and controls

Question 32

The recommended ratio of patch panels to horizontal cable management panels is _____ RU of patch panel to _____ rack unit (RU) of horizontal cable management panel.

a. One; one
b. One; two
c. Two; one
d. Two; three

Answer 32

a. One; one

p 3-16

The ratio of one RU patch panel to one RU horizontal cable manager plus one additional RU cable manager is recommended.

Question 33

In a telecommunications room (TR), the MINIMUM bottom edge height recommendation for mounting plywood on the wall is _____ above AFF.

a. 51 mm (2 in)
b. 152 mm (6 in)
c. 200 mm (8 in)
d. 305 mm (12 in)

Answer 33

c. 200 mm (8 in)

p 3-16

Mount plywood ≈200 mm (8 in) AFF to provide greater usability and minimize possible damage in the event of water ingress.

Question 34

You have been selected to do the telecommunications design on a new, single story building. The architect requires the size and location of the telecommunications rooms so their building design can proceed. From the items listed below (all of which are required for the design), which one is the logical starting point in order to provide the architect with a size and location for the room?

a. Determine where the entrance facility will be
b. Determine the number of their locations, and telecommunications services needed
c. Determine the power, HVAC, electrical, and security requirements for the room
d. Determine future growth and other requirements

Answer 34

b. Determine the number of their locations, and telecommunications services needed

p 4-38

Whenever possible, determine the different service requirements first. It is often convenient to group similar services together in categories (e.g., voice systems, LAN, and other digital connections). Then, identify the individual media types and projected quantities required within each group.

Question 35

A building has a floor space of 16.7 m (55 ft) by 45 m (150 ft) with a common area measuring 9.17 m (30 ft) by 13.7 m (45 ft). How many individual work areas can be provided in the usable floor space?

a. 50
b. 58
c. 69
d. 77

Answer 35

c. 69

p 3-38

a. Usable space = 8,250 ft^2 - 1,350 ft^2 = 6,900 ft^2
b. 6,900 ft^2/ 100 ft^2 = 69 work areas
c. Added step - 69 spaces x 0.75 ft^2 = 51.75 ft^2 = ER size. However, note, if there are fewer than 200 work areas, the ER shall be no less than ≈15 m2 (160 ft^2).
d. Therefore, ER size should = minimum of 160 ft^2

Question 36

The MINIMUM recommended lighting requirement in a telecommunications room (TR) at the point of cable terminations is:

a. 150 lux
b. 300 lux
c. 500 lux
d. 750 lux

Answer 36

c. 500 lux

p 3-9

Providing a minimum of ≈500 lx (46 foot-candles) of lighting in the horizontal plane and ≈200 lx (18.6 foot-candles) in the vertical plane, measured ≈1 m (3.28 ft) above the finished floor in the middle of all aisles between cabinets and racks.

Question 37

On a survey of one of your client’s buildings, you discover that one of the TRs, housing a considerable quantity of switching equipment, is at 24 degrees C (75 degrees F) with a relative humidity of 59 percent. This is considered to be:

a. Within the normal range of temperature and humidity
b. High temperature and normal humidity
c. Normal temperature and high humidity
d. High temperature and high humidity

Answer 37

c. Normal temperature and high humidity

Question 38

At a minimum, convenience receptacles in an ER or TR are to be located _____ AFF.

a. 150 mm (6 in)
b. 300 mm (12 in)
c. 375 mm (15 in)
d. 450 mm (18 in)

Answer 38

a. 150 mm (6 in)

p 3-6

Separate duplex or quad convenience receptacles (e.g., for tools, field test instruments):
–– Located at least ≈152 mm (6 in) AFF.
–– Placed at ≈1.83 m (6 ft) intervals around perimeter walls.

Question 39

Which of the following types of conduit uses set screw couplings and connectors?

a. RMC
b. EMT
c. IMC
d. Schedule 80 PVC

Answer 39

b. EMT

p 4-43

Setscrew or compression-type couplings and connectors are used to install EMT.

Question 40

A single outlet utilizing a dedicated phase, neutral, and ground conductor is the definition for which of the following?

a. Feeder circuit
b. Ground fault receptacle
c. Dedicated branch circuit
d. “Daisy-chained” series of receptacles

Answer 40

c. Dedicated branch circuit

p 3-46

A dedicated branch circuit serves a single outlet utilizing a dedicated phase, neutral, and ground conductor

Question 41

You are placing two 423 mm (19 in) relay racks with a 152 mm (6 in) vertical management panel on each end and a 12 in vertical cable management panel between the racks. The rack lineup begins in the middle of the room. What is the MINIMUM room size required?

a. 1.83 m (6 ft) x 2.4 m (8 ft)
b. 2.1 m (7 ft) x 2.4 m (8 ft)
c. 2.4 m (8 ft) x 2.4 m (8 ft)
d. 2.4 m (8 ft) x 3.0 m (10 ft)

Answer 41

d. 2.4 m (8 ft) x 3.0 m (10 ft)

p 3-11

Minimum telecommunications space for this setup is ≈3 m (10 ft) by ≈2.4 m (8 ft).

Question 42

The RECOMMENDED balanced twisted-pair cable for building backbone cabling consists of _____ round solid copper conductors with a nominal characteristic of 100 ohm.

a. 20-24 AWG
b. 22-26 AWG
c. 23-24 AWG
d. 24-22 AWG

Answer 42

d. 24-22 AWG

p 4-38

The recommended balanced twisted-pair cable for building backbone consists of 24 AWG or up to 22 AWG round, solid copper conductors with a nominal characteristic impedance of 100 ohm.

Question 43

A telecommunications enclosure should serve an area not greater than:

a. 223 m2 (2400 ft2)
b. 334 m2 (3600 ft2)
c. 446 m2 (4800 ft2)
d. 465 m2 (5000 ft2)

Answer 43

b. 334 m2 (3600 ft2)

p 3-37 - 331

A TE should serve an area not greater than ≈334 m2 (3600 ft2). Size the TE to accommodate immediate requirements and foreseeable growth.