TDMM Chapter 12 Flashcards
Easement
A right acquired by one party to used land beloning to another for a specific purpose
HH
Handhole
Innerduct
Non metallic duct placed in a larger pathway
MH
Manhole
NI
Network Interface
OSP
Outside Plant
Service Diversity
The palcing of alternate facilities to temporarily replace main system in case of failure
(two internet services)
Underground Facilities
Cables in underground conduit with manholes, handholes or pull boxes to access them
Name three critical factors to consider when planning for maintenance and future growth for a facility where campus backbone cables exist
- Familiarity with routes
- Working and Spare capacity
- Cable composition
Name five advantages of underground conduits
- Provide out of site service
- Adaptable for future growth
- Economical over long life
- Provide cable protection
- Minimizes repairs needed
Name four disadvantages of underground conduits
- High installation cost
- Require careful planning
- Possible path for water or gas to enter building
- More installation time than aerial or direct bury
Name three advantages of direct bury
- Provide out of site service
- Low installation cost
- Easy to move around obstructions
Name two disadvantages to direct bury conduit
- inflexible for future changes
- No extra cable protection
Name two advantages of aerial pathways
- Quick installation
- Readily accessible
Name five disadvantages of aerial pathways
- Ugly
- Require clearances for people and traffic
- Could damage building exterior
- Environmental conditions could damage
- Issues when poles are owned by others
Name four ways to bring balanced twisted pair cable onto a customers property
- Underground entrances
- Buried entrance
- Aerial entrances
- Tunnel systems
What factors are used to determine how many conduits and how large the conduits need to be for a given telecom service entrance
The number, size and types of cable to be used to serve the telecom service entrance
What are BICSIs recommendations for the number and size of conduits for each telecom service entrance point?
Four 4” conduits, with at least one spare
Why are innerducts recommended when optical fiber cables will be used inside conduits?
Innerduct ensures the maximum amount of cables can be placed in the conduit
Why is a copper conductor added to a condiot that contains fiber?
For locating purposes
Why would an access provider and customer owned cabling need to share a telecom service entrance?
To reduce installation costs
Name three risks associated with sharing an entrance conduit
- Reduce ability to provide extra cable into the EF
- Could damage cables with improper installation
- May not be permitted by access provider or AHJ
True or False
The AP is required to build the EF for any facility where the AP supplied the conduit from the property line to the building
False
How many 90 degree bends can be included between pulling points when installing underground entrances?
No more than two
True or False
A 90 degree bend may be exceeded if innerduct is included in the conduit
False
How many conduits should a property owner provide from a point in the building to the property line if the building is not on the property line?
Two or More
Whom should you call before digging the pathway for direct bury cable?
Local underground utilities center
Name three methods that should be used to prevent a trench from caving in
- Shoring
- Sloping
- Stepping
What is the maximum depth for the lower steps in a trench that is deeper than 5ft?
4ft
What is the minimum clearance from the edge of an excavated dirt pile to the nearest edge of a stepped trench that is deeper than 5ft?
2ft
What should be done to prevent a sunken trench appearance after the trench is refilled with excavated dirt?
Tamped down then checked again later
Name two limitations for the use of an aerial entrance in a small building
- Less than 300 pair and 100ft in length
- No other telecom facility entrances
Name five problems that make aerial entrances undesirable
- Lack of mechanical protection for the facility
- Ugly
- Clearance requirements
- Storm loading requirements
- Path of electrical exposure
When an aerial entrance is used, what is the maximum space permitted between the last pole and the building?
100ft
What is slack span construction?
A method of aerial cable installation that reduces tension
What is one of the main safety considerations associated with designing an aerial entrance?
Proper clearances and separation from electrical power lines
When the small diameter drop method is used to attach aerial cable to a building, what is used to support the cable?
A drop hook attached to a conduit mast
When should the small diameter drop method be used?
When there are only minimal circuit requirements
What is the maximum distance an aerial cable amy extend above the roof line?
4in
What is a campus arrangement?
A large tract of land with multiple buildings rather than one high rise building
True or False
Individual buildings in a campus arrangement may be treated as stand alone projects
True
True or False
If only one tenant occupies a campus arrangement complex, the main AP or WAN terminal for the complex may be located in one of the buildings?
True
True or False
An easement should be applied for after excavation work on private property is finished
False
What type of easement must be obtained when adjacent property owners will be affected by the work?
A perpetual easement
How are utility lines typically marked after they are located?
With marker paint, flags and stakes
Name six negative consequences of utlity disruption
- Injury
- Service outage
- Heavy fines for disrupting contractor
- Heavy construction fees
- Damage to property
- Loss of revenue for business
What telephone number is used in the united states to help companies locate underground facilities?
811
True or False
All utlities are required to participate in local one call systems?
False
What is the most critical factor to consider when you are determining the necessary level of service diversity?
Balance cost versus risk
When does full route diversity occur?
When there is a one hundred percent physically separated route such that the damage to the first route cannot affect the second route
Where should the ICT designer consider installing dual service entrances?
In buildings that provide mission critical continuous services
True or False
OSP cables are typically unlisted
True
Where does BICSI recommend that unlisted OSP cable be terminated or transitioned to listed cable?
As close as practical to the building entrance
What may be done to extend the point of entrance when bringing unlisted OSP cable into a building?
Place the entire length of incoming cable within a conduit
What is the minimum required diameter for a post that is being installed to protect termination equipment?
4in
How far should a post that is being installed to protect termination equipment extend AFF?
At least 42in
What grade of plywood is required for the walls of spaces where OSP cables will be terminated?
AC Grade or better
What determines the size of the room that will be used for terminating OSP cables?
- Type of facility
- Terminating hardware selected
- Necessity for electrical protection
Name four requirements for the door to the dedicated terminating space for OSP cable
- Open outward
- Be lockable with access control
- Have the same fire rating as the room wall
- Be at least 3ft wide by 6.5ft tall
How far should conduits entering a basement terminate from the finished wall?
4in
How far should conduits that enter from below grade extend above the finished floor?
4in
How far should conduits that enter through the ceiling terminate below the finished ceiling?
4in
Why should the end of the conduit that is inside of the building be sealed?
To prevent rodents, water, gas from entering the building
What is the point of connection between the AP network and private network?
Network Interface (NI) / Demarcation Point (DP)
What is the main advantage of using a centralized NI panel or housing?
Offers the AP and private network owners a single convenient test location for all premesis circuits
What is a possible disadvantage of locating a centralized NI panel in a secured area?
Access could be inconvenient if security or building engineers have to unlock panel
What is a possible disadvantage of locating a centralized NI panel in an unsecured area?
Privacy and Security could be compromised
What is soft digging?
Locating underground facilities through vacuum excavation
Name three methods for locating underground facilities
- Electronic
- Water vacuum
- Air vacuum
What is the purpose of warning tape?
Helps prevent accidental dig up
What type of warning tape should be used with fiber?
Detectable warning tape
What is the recommeded depth of a trench?
24in from top of cable to final grade
What is the minimum separation that must be maintained between a gas pipe and telecom cables when they cross in a trench
6in
What is the minimum separation between a street railway and telecom cabling in a trench
3.28ft
Why is a backhoe considered to be the most appropriate way to dig large trenches for multiple ducts or cables?
It requires work area to be fenced in after hours, keeps everything safer
Name four disadvantages with using a backhoe to dig trenches
- Requires frequent repositioning
- Space required around trench
- Extensive surface restoration
- Restriction to open areas
Name three alternatives to the traditional backhoe method for placing underground facilities
- Compact trencher
- Vibratory plow
- Horizontal directional drilling
Why are different types of transmission media separted when they are installed in the same underground pathway?
Separation provides:
- Ready identification
- Individual protection
- Individual growth potential
How can you protect conduit that passes under roads, driveways or railroad tracks?
Encase in concrete
What should be done to prevent conduits from shearing?
Extend sleeves through walls into the undisturbed earth
Name four types of corrosion resistant conduit
- Fiberglass
- Concrete
- Rigid Galvanized Metal
- Rigid and non rigid metal
How is most conduit listed?
By trade size
How many covers are required for an MH that measures between 12ft and 20ft long?
Two
How many covers are required for an MH that is longer than 20ft?
Three
What marking is typically used for the cover of a telephone MH?
T
What does an S marking on an MH represent?
Signal
What does an C marking on an MH represent?
Communication
Where should the number for an MH be placed?
On the inside collar above the first step
Name three benefits of placing main conduit entry points at opposite ends of an MH
- More organized cable
- Maximizes working space
- Premits splaying the entry points
What is the strength requirement for concrete using cast in place manholes?
3500 psi
Why should precast MH be used whenever possible?
Uniformity, economy and installation efficiency
Name two instances when site cast MHs should be used
- Size exceeds precast availability
- Obstructions prohibit use of precast
Name four factors that should be considered when selecting the permanent location for pole lines
- Future road widening
- Expansion of other utlities
- Special problems
- Safety and convenience of workers and public
Name three considerations for pole design
- Pole line classification
- Storm loading
- Clearance requirements
When should self supporting cable be used instead of lashed?
- If available in required size
- No existing strand
- New cable cannot be lashed to an existing
- Adequate space for future growth
What is the basis of pole class designations?
Design load not exceeding a percentage of the breaking strength
What type of loading refers to wind pressure on the attachments and aboveground portion of the pole?
Transverse storm loading
What is vertical loading?
The weight of the attacments and vertical components of the tension in guyed poles
What can create a bending moment on an aerial pole?
Eccentric loads or unbalanced tensions
