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FOA CFOS/O practice questions

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Question 1Fiber optic cable plant installation (outside plant)

When a single-mode outside plant cable is pulled through a duct, which practice best limits the tensile load actually reaching the fiber and buffer tubes?

  1. Pull on the aramid yarns while leaving the jacket free to slide
  2. Pull directly on the buffer tubes after stripping the jacket back one meter
  3. Attach the pull rope to the central strength member and pull from the cable end Correct answer.
  4. Pull on the outer jacket only, using a tight clove hitch behind the sheath

Explanation

In duct and conduit pulls, the load should be transferred to the central strength member or to the strength members designated by the manufacturer, so the fiber and buffer tubes carry essentially no tension. Pulling on the jacket, yarns alone, or bare buffer tubes concentrates stress on components not rated for the full installation load and can cause immediate or latent fiber damage.

Question 2Fiber optic cable plant installation (outside plant)

What is the primary purpose of placing a slack loop (service loop) at a splice closure in an outside plant span?

  1. To provide spare fiber for re-splicing and for closure re-entry Correct answer.
  2. To reduce the optical loss of the splices inside the closure
  3. To balance the number of fibers in each buffer tube
  4. To increase the cable's rated tensile strength

Explanation

Slack coils stored at closures and pedestals give technicians enough spare length to reopen the closure, re-terminate, or re-splice without pulling new cable. Slack has no meaningful effect on splice loss, tensile rating, or fiber counts per tube.

Question 3Fiber optic cable plant installation (outside plant)

Which condition most commonly justifies selecting an armored, rodent-resistant cable for a direct-buried outside plant route?

  1. The route terminates at an active optical distribution frame
  2. The route passes through soil where gnawing animals are known to be active Correct answer.
  3. The route crosses a body of water
  4. The route is installed in a metallic conduit under a roadway

Explanation

Armor and hardened sheath designs are specified where rodents, insects, or abrasive soil threaten the cable, because the metallic or dielectric armor resists penetration. Water crossings call for specialized submerged cable, conduit installation already provides mechanical protection, and the termination point does not drive burial protection.

Question 4Fiber optic cable plant installation (outside plant)

In an outside plant trench, why is warning tape or a tracer wire typically installed above the direct-buried cable?

  1. To provide tensile support to the buried cable
  2. To bond the cable armor to the local grounding grid
  3. To allow future locating and to warn excavators before they reach the cable Correct answer.
  4. To carry the optical signal in parallel with the cable

Explanation

A tracer wire or detectable marker lets locating crews find the buried plant, and warning tape alerts diggers before they contact the cable. Neither element carries signal, provides tensile support, or serves as the primary grounding bond.

Question 5Fiber optic cable plant installation (outside plant)

Which document governs the minimum burial depth for a direct-buried fiber optic cable on a public right-of-way?

  1. The applicable local code, franchise agreement, or owner standard for that route Correct answer.
  2. The optical time-domain reflectometer test report
  3. The splice closure installation guide
  4. The cable manufacturer's data sheet alone

Explanation

Burial depth requirements come from the governing code, right-of-way agreement, or the network owner's construction standards, which may vary by jurisdiction and surface type. Manufacturer documents describe the product, not legal depth, and test reports record results after installation.

Question 6Fiber optic cable plant installation (outside plant)

When installing an aerial fiber cable on a new strand, which hardware is used to attach the cable so that it is supported without over-clamping the sheath?

  1. A stainless steel band tightened to the strand
  2. Aramid yarn tied to the strand at midspan
  3. A spiral or formed-wire lashing wire applied by a lasher Correct answer.
  4. A cable tie cinched at each pole

Explanation

Aerial cable is normally lashed to the supporting strand with lashing wire applied by a lasher, which distributes support along the span and limits point loading. Bands, ties, and yarn knots create localized stress and are not standard aerial support methods.

Question 7Fiber optic cable plant installation (outside plant)

What is the main reason for maintaining the specified minimum bend radius during outside plant cable installation?

  1. To keep the cable from exceeding its rated attenuation at long wavelengths
  2. To match the numerical aperture of the connected equipment
  3. To prevent macrobending loss and mechanical damage to the fiber Correct answer.
  4. To ensure the cable fits inside standard splice trays

Explanation

Tight bends cause macrobending loss and can crack fiber or distort the buffer tubes, so manufacturers specify a minimum bend radius for loaded and unloaded conditions. Attenuation ratings and numerical aperture are fiber properties, and tray fit is a separate packaging concern.

Question 8Fiber optic cable plant installation (outside plant)

A crew is asked to install cable through a duct that is partially collapsed midway. Which action is appropriate before attempting the pull?

  1. Rod and prove the duct, then clear or re-route around the obstruction Correct answer.
  2. Cut the cable at the obstruction and splice it inside the duct
  3. Lubricate the cable and pull at maximum speed
  4. Increase pull tension until the cable passes the obstruction

Explanation

Ducts must be proved and cleared before pulling; a collapse will otherwise cause excessive tension, sheath damage, or a stuck cable. Raising tension, speeding up the pull, or leaving a splice inside a duct all violate accepted installation practice.

Question 9Fiber optic cable plant installation (outside plant)

During a long duct pull, the crew notices the pulling line tension rising steadily. Which technique is the accepted way to reduce tension without exceeding cable limits?

  1. Install intermediate assist pulls or pull from both ends toward a midpoint Correct answer.
  2. Wet the rope with water to reduce friction
  3. Pull faster so the cable spends less time in the duct
  4. Reduce the number of lubricant applications

Explanation

Intermediate assists or bidirectional pulling shorten the effective pull length and keep tension within the cable's rated limit. Water is not a substitute for proper cable lubricant, reducing lubricant increases friction, and pulling faster raises tension rather than lowering it.

Question 10Fiber optic cable plant installation (outside plant)

A direct-buried cable must cross beneath a paved road. Which method best protects the cable while allowing future replacement?

  1. Bury the cable at half the normal depth to shorten the trench
  2. Place the cable inside a split splice closure under the pavement
  3. Install a conduit or sleeve under the roadway and pull the cable through it Correct answer.
  4. Lay the cable directly in the trench backfill under the pavement

Explanation

A bore or sleeve under a paved surface protects the cable from traffic loads and permits replacement or additional cables without cutting pavement. Direct burial under pavement, reduced depth, and enclosing the cable in a closure all compromise protection or access.

Question 11Fiber optic cable plant installation (outside plant)

What is the correct handling of a cable end that will remain unterminated overnight at an outside plant site?

  1. Strip the jacket back to let the fibers air dry
  2. Tape it loosely and lay it in standing water
  3. Seal it with a manufacturer-approved end cap and secure it above grade Correct answer.
  4. Leave it open so any moisture can drain out

Explanation

Open cable ends wick moisture into the core, so ends must be sealed with an approved cap and stored where water cannot enter. Leaving ends open, submerging them, or stripping the jacket all invite water ingress and later loss.

Question 12Fiber optic cable plant installation (outside plant)

Which test is performed on a completed outside plant span to verify that the installed cable and splices meet the loss budget before acceptance?

  1. Tensile pull test on the installed span
  2. Continuity check with a visible fault locator only
  3. Insulation resistance test on the armor
  4. Optical time-domain reflectometer (OTDR) trace plus bidirectional insertion loss measurement Correct answer.

Explanation

Acceptance testing uses OTDR traces and bidirectional insertion loss measurements to confirm splice and span loss against the budget. A visual fault locator only shows gross breaks, insulation resistance applies to metallic conductors, and pull testing after installation would risk damage.

Question 13Fiber optic cable plant installation (outside plant)

A splice closure is being installed in a handhole that periodically fills with water. What closure characteristic is most important?

  1. A re-enterable, watertight closure rated for submerged or wet locations Correct answer.
  2. A closure made of UV-stabilized plastic
  3. A closure with the largest available splice tray count
  4. A pressurizable closure body

Explanation

Closures in wet or periodically flooded handholes must be watertight and rated for that environment so water cannot reach the splices. Pressure, tray count, and UV stabilization address other concerns and do not prevent water ingress.

Question 14Fiber optic cable plant installation (outside plant)

Why must buffer tubes be identified and fibers assigned according to the cable's color code during splicing?

  1. To reduce the number of trays required in the closure
  2. To maintain consistent fiber assignments across the network for testing and troubleshooting Correct answer.
  3. To increase the cable's resistance to moisture
  4. To keep splice loss below 0.1 dB per splice

Explanation

Consistent color-code and tube assignment ensures that a fiber at one end maps predictably to the same fiber at the other, which is essential for testing, records, and future rearrangements. It does not set splice loss, moisture performance, or tray count.

Question 15Fiber optic cable plant installation (outside plant)

A crew is installing aerial cable where the strand sag has not yet been set to final tension. What is the correct sequence?

  1. Lash the cable first, then tension the strand to final sag
  2. Install the cable without lashing and tension the strand later
  3. Lash the cable and tension the strand simultaneously
  4. Set the strand to final tension and sag, then lash the cable Correct answer.

Explanation

The supporting strand must be tensioned to its final sag before lashing so the cable is supported at its design position and the lashing does not carry load. Lashing first or working simultaneously can trap the cable in the wrong geometry and overload the lashing.

Question 16Fiber optic cable plant installation (outside plant)

What does a positive pressure test on a newly installed air-pressurized cable system indicate during commissioning?

  1. The cable has failed and must be replaced
  2. The fiber attenuation is below the design budget
  3. The sheath and closures hold pressure within the specified limit, indicating an intact envelope Correct answer.
  4. The splice loss is within tolerance

Explanation

Pressure testing verifies that the cable sheath, closures, and fittings form a sealed envelope that can hold air within the specified leak limit. It says nothing directly about attenuation or splice loss, and a passing result indicates the sheath is intact rather than failed.

Question 17Fiber optic cable plant installation (outside plant)

An installer must place cable in a duct bend that cannot meet the standard bend radius. Which approach is most appropriate?

  1. Reduce the cable diameter by removing the outer jacket
  2. Use a manufactured sweep or bend limiter that maintains the required radius Correct answer.
  3. Heat the cable jacket to make it more flexible
  4. Force the cable through and rely on the buffer tubes to absorb the bend

Explanation

Where geometry cannot meet the minimum bend radius, a proper sweep or bend-limiting fitting restores the required radius and protects the fiber. Forcing the cable, heating the jacket, or stripping the sheath compromises the cable and violates installation limits.

Question 18Fiber optic cable plant installation (outside plant)

Which factor most directly determines the required number of intermediate pull points for a long underground duct installation?

  1. The number of fibers in the cable
  2. The calculated pull tension versus the cable's rated installation tension Correct answer.
  3. The type of splice closure to be used
  4. The color code of the buffer tubes

Explanation

Pull points are spaced so that calculated tension, including friction and bend effects, stays below the cable's rated installation tension. Color code, fiber count, and closure type do not drive tension calculations for the pull.

Question 19Fiber optic cable plant installation (outside plant)

A buried cable route crosses a drainage ditch that carries seasonal runoff. Which installation measure best protects the cable?

  1. Provide additional depth, conduit, or armor at the crossing as required by the owner's standard Correct answer.
  2. Reduce the burial depth to keep the cable above the water table
  3. Splice the cable at the ditch to allow future replacement
  4. Lay the cable on the ditch bed without cover

Explanation

Water crossings and drainage features require extra protection such as greater depth, conduit, or armor per the governing standard to resist erosion and loading. Reducing depth, leaving cable uncovered, or placing a splice in the ditch all increase failure risk.

Question 20Fiber optic cable plant installation (outside plant)

During an OTDR acceptance test, a splice shows elevated loss in one direction but acceptable loss in the reverse direction. What is the correct interpretation?

  1. The splice should be evaluated using bidirectional measurements and averaged or compared against the limit Correct answer.
  2. The splice is acceptable because one direction passed
  3. The OTDR is faulty and the test should be discarded
  4. The fiber color code was assigned incorrectly

Explanation

OTDR splice loss readings can differ by direction because of backscatter differences between fibers, so bidirectional measurements are averaged or otherwise evaluated per the test plan. A single direction is not conclusive, discarding the test is unjustified, and color assignment does not affect loss.

Question 21Fiber optic cable plant installation (outside plant)

Aerial cable is to be installed on a strand that already carries another cable and a telephone line. What is the main reason to verify the strand's load capacity before adding the new cable?

  1. To ensure the added weight and ice/wind loads stay within the strand's design strength Correct answer.
  2. To confirm the strand color matches the new cable
  3. To determine the splice tray count
  4. To set the OTDR pulse width

Explanation

Adding cable increases dead load and wind and ice loading on the strand and poles, so the strand's rated capacity must be checked to avoid excessive sag or failure. Color, tray count, and test settings are unrelated to structural capacity.

Question 22Fiber optic cable plant installation (outside plant)

A direct-buried cable must pass near a buried fuel pipeline. Which practice is most appropriate before excavation?

  1. Reduce the trench depth to avoid the pipeline corridor
  2. Proceed with trenching and rely on the cable armor for protection
  3. Call for utility locating and pothole to confirm the pipeline's position before digging Correct answer.
  4. Install the cable above grade to avoid the conflict

Explanation

Excavation near existing utilities requires locating and confirming the other utility's position, typically by potholing, before digging to prevent damage and safety incidents. Relying on armor, changing depth arbitrarily, or going above grade does not address the conflict safely.

Question 23Fiber optic cable plant installation (outside plant)

A long span is installed with excessive sag compared with the design value. Which consequence is most directly expected?

  1. Higher fiber count per buffer tube
  2. Lower splice loss at the closures
  3. Increased tension on the cable and greater clearance and loading concerns Correct answer.
  4. Reduced need for lashing wire

Explanation

Excessive sag changes the mechanical geometry, altering tension distribution and reducing clearance, and it can worsen wind and ice loading behavior. Sag does not change splice loss, fiber count, or lashing requirements in the direction described.

Question 24Fiber optic cable plant installation (outside plant)

When pulling cable through a duct, why is a swivel placed between the pulling rope and the cable pulling eye?

  1. To prevent the rope's twist from being transferred to the cable Correct answer.
  2. To increase the pulling tension available
  3. To measure the cable's attenuation during the pull
  4. To bond the cable armor to ground

Explanation

A swivel isolates rope twist so the cable does not rotate and twist its buffer tubes during the pull. It does not increase tension, measure optical loss, or provide electrical bonding.

Question 25Fiber optic cable plant installation (outside plant)

Which practice is recommended when coiling excess outside plant cable for storage at a pedestal?

  1. Store the coil buried loosely in the backfill
  2. Fold the cable back on itself and tape the fold
  3. Coil it tightly around a small radius to save space
  4. Coil it at or above the minimum bend radius and secure it to a support Correct answer.

Explanation

Stored slack must respect the cable's minimum bend radius and be supported so it is not damaged by traffic or maintenance. Tight coiling, folding, or loose burial all risk macrobending loss and mechanical damage.

Question 26Fiber optic cable plant installation (outside plant)

Which type of outside plant cable is designed for installation by pulling through a conduit, and typically has a small diameter with a low-friction jacket?

  1. Indoor riser cable
  2. Duct cable Correct answer.
  3. Aerial figure-eight cable
  4. Direct-buried armored cable

Explanation

Duct cable is manufactured with a compact, low-friction outer jacket and appropriate stiffness so it can be pulled or jetted through conduits over long distances. Direct-buried and aerial designs have different jackets, strength members, or messenger attachments. The duct cable design balances pulling performance against protection from the conduit environment.

Question 27Fiber optic cable plant installation (outside plant)

A crew is placing a loose-tube outside plant cable that will be installed in a wet duct environment. Which cable feature is most important to confirm before installation?

  1. The cable jacket is colored for identification
  2. The cable has a dielectric strength member
  3. The cable contains a longitudinal water-blocking compound or dry water-swellable tape Correct answer.
  4. The cable is rated for plenum use

Explanation

In wet duct environments, water can enter through jacket damage or open ends, so longitudinal water blocking (gel or swellable tape) is essential to prevent water migration along the cable core. Jacket color and strength-member material do not address water ingress. Plenum ratings relate to indoor fire performance, not outside plant moisture protection.

Question 28Fiber optic cable plant installation (outside plant)

During an outside plant installation, a crew must place cable through a series of manholes. Which practice best protects the cable from damage at each manhole entry?

  1. Apply grease to the manhole lip before pulling
  2. Pull the cable directly over the concrete manhole lip
  3. Tie the cable off at each manhole to reduce tension
  4. Use a cable guide or sheave at the manhole edge to control bend radius and abrasion Correct answer.

Explanation

Cable guides and sheaves keep the cable from rubbing on sharp concrete or metal edges and maintain the required bend radius at each entry point. Pulling directly over the lip risks jacket abrasion and excess bending. Tying off at each manhole interrupts the pull and can overstress the cable.

Question 29Fiber optic cable plant installation (outside plant)

Which document should an outside plant crew consult to determine the specified cable route, depth, and splice locations before beginning a new installation?

  1. The cable manufacturer's data sheet
  2. The network operations center's alarm log
  3. The construction drawings and specifications for the project Correct answer.
  4. The OTDR test report from a previous job

Explanation

Construction drawings and specifications define the approved route, burial depth, duct assignments, and splice point locations for the specific project. Manufacturer data sheets describe cable properties but not route design. OTDR reports and alarm logs reflect existing or completed systems rather than the planned installation.

Question 30Fiber optic cable plant installation (outside plant)

A crew is installing direct-buried cable and must place warning tape above the cable. What is the primary purpose of the warning tape?

  1. To alert future excavators to the presence of buried cable before they dig into it Correct answer.
  2. To mark the cable's color code at each splice
  3. To hold the cable in place within the trench
  4. To provide a conductive path for locating the cable

Explanation

Warning tape is placed above the buried cable to warn anyone excavating later that a cable is present, reducing the risk of accidental dig-ins. It does not provide mechanical restraint or locate the cable electrically. Locating is typically done with a metallic tracer wire or tone.

Question 31Fiber optic cable plant installation (outside plant)

A crew must install cable in a duct that is already occupied by another cable, leaving limited free space. Which practice is most appropriate?

  1. Remove the existing cable and reinstall both together
  2. Confirm the duct fill ratio and use a pulling lubricant compatible with both cables Correct answer.
  3. Pull the new cable at maximum speed to overcome friction
  4. Force the new cable through without lubricant to save time

Explanation

When a duct already contains cable, the remaining free space must be checked against the allowable fill ratio, and a compatible lubricant reduces friction and jacket damage. Forcing cable without lubricant or at excessive speed increases tension and abrasion risk. Removing an in-service cable is disruptive and unnecessary if fill allows installation.

Question 32Fiber optic cable plant installation (outside plant)

A crew is installing aerial cable on a strand and must bond the metallic strength member to the strand. Why is this bonding required?

  1. To keep the cable from sliding along the strand
  2. To increase the tensile strength of the strand
  3. To improve the optical loss of the fibers
  4. To provide electrical continuity for grounding and protect personnel and equipment from lightning or fault currents Correct answer.

Explanation

Bonding the metallic elements to the strand creates a continuous grounding path so that lightning or power fault currents are safely conducted to ground rather than damaging the cable or injuring personnel. Bonding does not add tensile strength or affect optical loss. Mechanical attachment to the strand is handled by lashing or clamps.

Question 33Fiber optic cable plant installation (outside plant)

A splice closure is being installed in a manhole where the cable enters through a duct. Which practice best prevents water from entering the closure along the cable?

  1. Leave the entry points open for drainage
  2. Fill the entire manhole with gravel
  3. Seal the cable entry points with a compatible sealing compound or grommet and ensure the cable jacket is clean Correct answer.
  4. Wrap the closure with tape only at the top

Explanation

Water commonly enters a closure along the cable jacket at the entry ports, so those ports must be sealed with the manufacturer's sealing system and the jacket cleaned for good adhesion. Taping only the top leaves the entry path open. Leaving entries open invites water ingress, and gravel does not seal the closure.

Question 34Fiber optic cable plant installation (outside plant)

A direct-buried cable route passes through soil with high rock content. Which installation method is most appropriate to protect the cable?

  1. Wrap the cable in warning tape before backfilling
  2. Bury the cable directly against the rock to save material
  3. Reduce the burial depth so the cable rests above the rock
  4. Place the cable in a duct or use a cushioned bedding layer of sand or screened soil Correct answer.

Explanation

Rocky soil can abrade or crush a direct-buried cable, so placing it in a duct or bedding it in sand or screened soil provides a protective cushion. Direct contact with rock risks jacket damage. Reducing depth increases damage risk, and warning tape does not protect against rock.

Question 35Fiber optic cable plant installation (outside plant)

A crew is installing a cable through a duct and the pulling eye begins to rotate as tension is applied. Which installation component is designed to allow this rotation while transmitting pulling force?

  1. A strand vise
  2. A breakaway link
  3. A cable guide sheave
  4. A swivel Correct answer.

Explanation

A swivel placed between the pulling rope and the pulling eye allows the cable to rotate and relieve torsional buildup while still transmitting pulling force. A breakaway link limits tension but does not permit rotation. Sheaves guide the cable, and a strand vise grips strand rather than allowing rotation.

Question 36Fiber optic cable plant installation (outside plant)

After an outside plant cable is installed, a crew must coil excess slack for storage at a pedestal. Which practice is most appropriate?

  1. Fold the cable sharply and tape it flat
  2. Cut the slack and discard it to avoid coiling
  3. Coil the slack tightly around a small radius to save space
  4. Coil the slack in a figure-eight or large loop that respects the minimum bend radius Correct answer.

Explanation

Excess cable should be stored in large loops or a figure-eight pattern that keeps every bend above the minimum bend radius, preventing fiber attenuation and long-term damage. Tight coiling or sharp folding can induce loss and break fibers. Discarding slack removes the ability to re-splice later.

Question 37Fiber optic cable plant installation (outside plant)

A crew is installing aerial cable and finds that the strand has not yet been tensioned to its final sag. What is the correct sequence?

  1. Install the cable without lashing, then tension the strand and lash
  2. Install and lash the cable, then tension the strand with the cable attached
  3. Lash the cable loosely, then tension the strand and leave the lashing loose
  4. Tension the strand to final sag first, then install the cable and lash it Correct answer.

Explanation

The strand should be brought to its final tension and sag before the cable is installed and lashed, so the cable follows the correct profile and the lashing is applied at proper tension. Tensioning after the cable is attached can damage the cable and produce incorrect sag. Loose lashing leaves the cable unsupported.

Question 38Fiber optic cable plant installation (outside plant)

A crew is preparing to pull cable through a long duct and must select a pulling lubricant. Which factor is most important in that selection?

  1. Compatibility of the lubricant with the cable jacket and duct material over the expected service life Correct answer.
  2. The brand name of the lubricant
  3. The color of the lubricant
  4. The viscosity of the lubricant at room temperature only

Explanation

The lubricant must be compatible with both the cable jacket and the duct material so it does not degrade either over time, while still providing adequate friction reduction. Color and brand are not performance criteria. Viscosity matters, but evaluating it only at room temperature ignores the range of installation conditions.

Question 39Fiber optic cable plant installation (outside plant)

A crew installing cable in a duct notices that the calculated pulling tension is approaching the cable's maximum allowable value midway through the pull. Which action is most appropriate?

  1. Add more lubricant only at the far end of the duct
  2. Increase pulling speed to finish the pull quickly
  3. Stop the pull and add an intermediate pull point or reduce friction before continuing Correct answer.
  4. Continue at the same tension to avoid stopping the pull

Explanation

When tension approaches the allowable maximum, the pull should be stopped and the setup changed, for example by adding an intermediate pull point or reducing friction, before the cable is overstressed. Increasing speed raises tension further. Continuing at the limit risks cable damage, and lubricating only at the far end does not reduce tension along the already-pulled section.

Question 40Fiber optic cable plant installation (outside plant)

A crew must install direct-buried cable across a paved rural road with light traffic. The local authority requires that the roadway remain open to traffic during the work, and the design calls for a rigid structure that protects the cable from vertical live loads. Which installation method best meets these requirements?

  1. Plowing the cable directly across the roadway shoulder at a shallower depth than the roadbed
  2. Attaching the cable to an existing utility pole line that crosses the road at right angles
  3. Directional boring beneath the roadway with the cable installed in a continuous rigid conduit or sleeve Correct answer.
  4. Open-cut trenching across the roadway with the cable bedded in sand and a steel plate cover

Explanation

Where a road must stay open and the design requires a rigid protective structure, trenchless methods such as directional boring place a conduit or sleeve beneath the roadway without cutting the pavement, and the cable is then pulled through that sleeve. This preserves traffic flow and gives the cable mechanical protection against live loads. Open cutting is used when excavation is permitted and traffic can be managed, while plowing and aerial placement do not provide the specified rigid crossing structure.

Question 41Outside plant fiber optic cable types and hardware

In outside plant construction, which cable designation indicates a loose-tube cable whose interstices are filled with a water-blocking compound to prevent moisture migration?

  1. Filled loose-tube cable Correct answer.
  2. Armored ribbon cable
  3. Figure-8 aerial cable
  4. Toneable drop cable

Explanation

A filled loose-tube design floods the tube and cable core with a water-blocking gel or compound, which stops water from traveling along the cable if the sheath is damaged. This is the standard OSP choice for buried and duct installations where moisture ingress is a real risk.

Question 42Outside plant fiber optic cable types and hardware

A dielectric OSP cable is specified for an installation where the cable will pass through an area with nearby high-voltage equipment and lightning exposure. What is the primary reason for choosing dielectric construction?

  1. It increases the maximum number of fibers per tube
  2. It allows the cable to be directly buried without any conduit
  3. It eliminates metallic current paths that could carry fault or lightning current Correct answer.
  4. It removes the need for a strength member

Explanation

Dielectric cables contain no metallic conductors or armor, so they cannot conduct lightning surge or power fault current along the route. That reduces the risk of damage to electronics and of hazardous potentials reaching personnel.

Question 43Outside plant fiber optic cable types and hardware

Which outside plant cable type is specifically designed for aerial installation by integrating the support messenger into the cable sheath?

  1. Figure-8 cable Correct answer.
  2. Low-smoke zero-halogen cable
  3. Submarine cable
  4. Single-tube breakout cable

Explanation

Figure-8 construction attaches the messenger wire to the cable with a web, so the assembly is installed in one pull and lashed or clamped as a unit. This saves a separate strand installation and a separate lashing pass.

Question 44Outside plant fiber optic cable types and hardware

What is the purpose of an FRP central strength member in a loose-tube OSP cable?

  1. To identify individual fibers by color
  2. To block water from entering the cable core
  3. To improve the cable's electrical grounding
  4. To provide tensile strength and limit strain on the fibers during installation Correct answer.

Explanation

The central strength member carries the pulling and tension loads so the optical fibers see minimal strain. FRP is used where a nonmetallic member is needed, and its stiffness also helps control bending behavior.

Question 45Outside plant fiber optic cable types and hardware

A technician must splice a single loose tube containing 12 fibers inside a pedestal-mounted closure. Which hardware component is used to fan out and protect the individual fibers as they leave the tube?

  1. A cable spacer
  2. A ground lug
  3. A splice tray with a tube-entry fan-out Correct answer.
  4. A messenger clamp

Explanation

A splice tray with a fan-out holds the tube entry and routes each buffered fiber into the tray while maintaining minimum bend radius. The tray also stores and protects the splices themselves.

Question 46Outside plant fiber optic cable types and hardware

Which cable hardware is used to attach an aerial OSP cable to a steel strand while allowing the cable to be tensioned and later adjusted?

  1. Suspension clamp Correct answer.
  2. Cable tie wrap
  3. Strand lashing wire
  4. Drive anchor

Explanation

A suspension clamp grips the cable and hangs it from the strand, supporting the cable weight while allowing controlled tensioning and adjustment. Lashing wire is a separate method that wraps cable to strand continuously.

Question 47Outside plant fiber optic cable types and hardware

In a direct-buried OSP installation, what is the main function of an armored sheath with corrugated steel tape?

  1. To reduce the cable's attenuation coefficient
  2. To provide rodent and mechanical protection for the fiber core Correct answer.
  3. To allow the cable to be used in plenum spaces
  4. To increase the cable's numerical aperture

Explanation

Corrugated steel tape armor resists crushing, rodent attack, and mechanical damage in buried environments. It is a protective layer, not an optical element.

Question 48Outside plant fiber optic cable types and hardware

Which term describes the hardware assembly that anchors the strength member of an OSP cable at a building entrance so cable tension is not transferred to the fibers?

  1. Splice case
  2. ONT enclosure
  3. Fiber distribution panel
  4. Cable grip and strength-member clamp Correct answer.

Explanation

A cable grip holds the cable while a strength-member clamp secures the aramid or FRP member to the building structure. This transfers tension to the building rather than to the fiber terminations.

Question 49Outside plant fiber optic cable types and hardware

A buried loose-tube cable must transition into a conduit at a handhole. Which hardware is typically used to protect the cable and seal the duct entry against water and debris?

  1. A duct plug with a cable seal Correct answer.
  2. A pedestal
  3. A splice tray
  4. A fiber connector

Explanation

A duct plug with a cable seal closes the annular space around the cable at the conduit entry, blocking water, gas, and debris from entering the duct. This is a routine OSP practice at handholes and vaults.

Question 50Outside plant fiber optic cable types and hardware

A route requires a cable to be placed in a duct that already contains two other cables, leaving limited free space. Which cable feature most directly determines whether the installation is feasible?

  1. Cable outside diameter relative to duct inside diameter Correct answer.
  2. Jacket color
  3. Number of rip cords
  4. Fiber core diameter

Explanation

Duct fill is governed by the ratio of cable outside diameter to duct inside diameter, which controls pulling friction and clearance. Even a high-fiber-count cable may fit if its outer diameter is small enough.