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BICSI OSP practice questions

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Question 1Outside Plant Design

In outside plant design, what is the primary purpose of a splice closure placed in a direct-buried cable run?

  1. To convert optical signals into electrical signals for testing
  2. To amplify the optical signal between distant buildings
  3. To provide primary lightning surge grounding for the cable
  4. To environmentally seal and mechanically protect joined cable ends Correct answer.

Explanation

A splice closure houses the spliced fibers and seals the joint against moisture, dust, and mechanical damage so the cable keeps its transmission integrity over its service life. It does not perform signal amplification, media conversion, or act as the grounding electrode.

Question 2Outside Plant Design

Which cable type is generally preferred for aerial installation because it carries its own tensile load without a separate messenger?

  1. Figure-eight self-supporting cable Correct answer.
  2. Indoor riser-rated cable
  3. Figure-eight aerial cable
  4. All-dielectric loose-tube cable

Explanation

Self-supporting aerial cable integrates a strength member that bears the span tension, so it can be strung between poles without a separate lashing wire or messenger strand. Standard dielectric loose-tube cable lacks that integrated support and needs separate support hardware.

Question 3Outside Plant Design

What is the standard minimum cover depth typically specified for direct-buried fiber optic cable under a light-duty pedestrian area?

  1. About 150 mm (6 in)
  2. About 1200 mm (48 in)
  3. About 600 mm (24 in)
  4. About 300 mm (12 in) Correct answer.

Explanation

Light-duty areas such as pedestrian walkways generally require roughly 300 mm of cover for direct-buried cable, while heavier vehicular areas demand greater depth. Deeper values apply where vehicle loading or frost considerations exist.

Question 4Outside Plant Design

Which document element in an OSP design defines the physical route, splice points, and cable quantities along a right-of-way?

  1. The acceptance test report
  2. The warranty certificate
  3. The route or outside plant plan drawing Correct answer.
  4. The bill of materials

Explanation

The route plan drawing shows the geographic path, structure locations, splice points, and cable lengths that define the physical build. Other documents support procurement, testing, or warranty rather than route geometry.

Question 5Outside Plant Design

What does the term 'span' refer to in an aerial outside plant design?

  1. The total length of cable on a single reel
  2. The vertical clearance above a roadway
  3. The number of fibers in a buffer tube
  4. The distance between two adjacent supporting poles Correct answer.

Explanation

A span is the horizontal distance between two consecutive pole supports, and it drives sag, tension, and strength-member selection. Reel length, fiber count, and clearance are separate design parameters.

Question 6Outside Plant Design

Why is a conduit bend radius limit important when designing an underground duct system?

  1. It controls the color coding of innerduct
  2. It sets the grounding resistance of the duct
  3. It prevents excessive pulling tension and cable damage during installation Correct answer.
  4. It determines the burial depth of the duct bank

Explanation

Excessive bend tightness raises pulling friction and sidewall pressure, risking cable jacket damage or fiber stress during installation. Designers keep bends within limits and use sweeps to control these forces.

Question 7Outside Plant Design

What is the main function of a pedestal in an underground OSP network?

  1. To supply backup electrical power to network equipment
  2. To house splices and provide access at a transition point above grade Correct answer.
  3. To measure optical loss during acceptance testing
  4. To terminate aerial messenger strand to the pole

Explanation

A pedestal brings a splice or service point above grade so technicians can access and maintain buried cable without excavation. It does not supply power, anchor aerial strand, or perform measurement.

Question 8Outside Plant Design

Which fiber type is most commonly specified for long-haul outside plant links requiring low attenuation at 1310 nm and 1550 nm?

  1. Multimode OM4 fiber
  2. Plastic optical fiber
  3. Single-mode fiber Correct answer.
  4. Multimode OM1 fiber

Explanation

Single-mode fiber offers low attenuation and no modal dispersion at 1310 nm and 1550 nm, making it the standard choice for long outside plant spans. Multimode grades are limited by modal dispersion over long distances.

Question 9Outside Plant Design

A designer must route cable between two buildings 800 m apart across a parking lot that cannot be trenched. Which approach best fits the constraint?

  1. Direct-buried cable laid on the pavement surface
  2. Indoor plenum cable in surface raceway
  3. Aerial span on poles or a messenger across the lot Correct answer.
  4. Buried cable at 150 mm depth without conduit

Explanation

When trenching is not feasible, an aerial route using poles or a messenger provides a supported path across the obstacle. Surface-laid or shallow cable would be exposed to damage and violate cover requirements.

Question 10Outside Plant Design

During a duct design, a run requires several 90-degree direction changes. What is the most appropriate design response to control pulling tension?

  1. Remove all innerduct to simplify the pull
  2. Reduce the duct diameter to lower friction
  3. Increase the number of cables pulled at once
  4. Add intermediate pull points or handholes between bends Correct answer.

Explanation

Intermediate pull points or handholes break long pulls into shorter segments, reducing cumulative bend friction and tension. Smaller ducts, larger bundles, and missing innerduct all increase pulling difficulty.

Question 11Outside Plant Design

A proposed aerial span crosses a residential street. Which design factor most directly governs the required attachment height on the poles?

  1. The minimum vertical clearance required over the roadway Correct answer.
  2. The number of splices in the span
  3. The color of the cable jacket
  4. The fiber count of the cable

Explanation

Codes and utility standards set minimum vertical clearances above roadways, so attachment height must satisfy that clearance plus sag. Fiber count, jacket color, and splice count do not set the height requirement.

Question 12Outside Plant Design

A designer is placing handholes along a long underground duct run. What is the primary design reason for their spacing?

  1. To increase the optical signal strength along the route
  2. To provide electrical grounding every 100 m
  3. To limit pulling length and provide splice or pull access Correct answer.
  4. To satisfy zoning color requirements

Explanation

Handholes are spaced to keep cable pulls within tension limits and to give access for splicing or future reconfiguration. They are passive access structures and do not amplify signals or provide grounding.

Question 13Outside Plant Design

When computing a fiber link loss budget, which combination of terms should be included?

  1. Only the transmitter output power
  2. Cable attenuation, splice losses, connector losses, and margin Correct answer.
  3. Cable weight per meter and reel length
  4. Only the receiver sensitivity

Explanation

A loss budget sums fiber attenuation over distance, splice and connector losses, and a design margin so the link stays within the receiver's dynamic range. Transmitter power alone or receiver sensitivity alone is incomplete.

Question 14Outside Plant Design

A splice closure will be installed in a wet, below-grade vault. Which closure attribute is most critical for long-term reliability?

  1. The number of cable entry ports only
  2. Rated environmental sealing against water ingress Correct answer.
  3. Aesthetic color matching the vault
  4. The brand of the splice protection sleeves

Explanation

In a wet vault the closure must maintain a watertight seal to prevent moisture reaching the splices, which would degrade optical performance. Color, port count, and sleeve brand are secondary to sealing integrity.

Question 15Outside Plant Design

Why might a designer specify armored cable for a direct-buried route crossing a landscaped area subject to occasional digging?

  1. To eliminate the need for any splice closures
  2. To increase the optical bandwidth of the fiber
  3. To provide additional mechanical protection against abrasion and rodent damage Correct answer.
  4. To reduce the cable's bend radius requirement to zero

Explanation

Armor adds a metallic or dielectric layer that resists abrasion, crushing, and rodent attack in areas where excavation may occur. It does not change optical bandwidth, remove bend limits, or eliminate splices.

Question 16Outside Plant Design

In an OSP design, what is the purpose of a slack loop or service loop at a handhole or building entrance?

  1. To provide spare cable length for future splicing or retermination Correct answer.
  2. To reduce the cable attenuation at 1550 nm
  3. To shorten the overall route length
  4. To improve the grounding of the cable shield

Explanation

Slack loops store extra cable so technicians can re-splice, relocate, or repair without pulling new cable. They do not change attenuation, grounding, or route length in a beneficial optical sense.

Question 17Outside Plant Design

A designer must choose between a shorter route through an environmentally sensitive wetland and a longer route along a road right-of-way. Which consideration most strongly favors the longer route?

  1. Shorter installation schedule
  2. Lower cable attenuation on the longer path
  3. Higher fiber count available on the road route
  4. Reduced permitting and environmental impact risk Correct answer.

Explanation

Avoiding sensitive habitats reduces environmental permitting burden and long-term risk, which often outweighs added cable length. Attenuation and fiber count are not inherently improved by the road route, and the longer path is not shorter to install.

Question 18Outside Plant Design

Which practice best protects buried cable at a point where it rises from the ground into a pole or building?

  1. Using a protective riser guard or conduit and securing the cable Correct answer.
  2. Burying the transition point deeper than the duct
  3. Leaving the cable unsupported above grade
  4. Removing the cable jacket at the transition

Explanation

A riser guard or conduit shields the cable from mechanical damage and UV exposure at the above-grade transition, and proper securing prevents strain. Unsupported or stripped cable at that point is vulnerable.

Question 19Outside Plant Design

What is the role of innerduct within a larger underground conduit?

  1. To subdivide the conduit and protect individual cables or future capacity Correct answer.
  2. To carry electrical power alongside the fiber
  3. To increase the optical signal strength
  4. To provide the primary grounding path for the duct bank

Explanation

Innerduct divides a large conduit into smaller protected pathways, allowing multiple cables and future additions without re-excavation. It is not a power carrier, grounding path, or signal amplifier.

Question 20Outside Plant Design

A designer is evaluating whether to use a directional bore versus open-cut trenching for a road crossing. Which factor most favors directional boring?

  1. The need to minimize surface disruption to traffic and pavement Correct answer.
  2. A desire to reduce the number of splices in the crossing
  3. The need to lower the fiber count in the crossing
  4. The requirement to install cable at the shallowest possible depth

Explanation

Directional boring installs duct beneath a road without cutting pavement or disrupting traffic, which is its main advantage at crossings. It does not itself reduce splices, allow shallower depth, or change fiber count.

Question 21Outside Plant Design

Why is bonding and grounding of metallic cable components important in an OSP design?

  1. To equalize potential and protect personnel and equipment from fault currents Correct answer.
  2. To reduce the cable's physical weight
  3. To increase the optical power launched into the fiber
  4. To eliminate the need for splice closures

Explanation

Bonding and grounding equalize electrical potential on metallic members, limiting hazardous voltages from lightning or power faults and protecting people and equipment. They have no effect on optical launch power, cable weight, or splice needs.

Question 22Outside Plant Design

A route must cross a river. Which design approach is generally most appropriate for a permanent fiber crossing?

  1. Laying cable on the riverbed surface without protection
  2. Stringing standard aerial cable across the water on existing trees
  3. Using a dedicated underwater cable or a bored/attached crossing designed for the conditions Correct answer.
  4. Burying cable at 150 mm in the riverbank only

Explanation

River crossings require a purpose-designed solution such as a submarine cable or a bored or structure-attached crossing engineered for scour, current, and anchoring. Unprotected or improvised methods risk failure.

Question 23Outside Plant Design

A designer must decide splice point locations along a long underground route. Which principle best guides that decision?

  1. Place splices at convenient access structures while respecting cable reel lengths and loss budget Correct answer.
  2. Place all splices at the midpoint regardless of access
  3. Locate splices only where the cable changes color
  4. Maximize splice count to improve reliability

Explanation

Splice points should coincide with accessible structures and be arranged so cable segments match reel lengths while keeping total splice loss within budget. Arbitrary or excessive splicing adds loss and maintenance burden.

Question 24Outside Plant Design

What is the primary reason for maintaining specified separation between communications duct and electrical power duct in a shared trench?

  1. To reduce electromagnetic interference and safety hazards Correct answer.
  2. To keep the fiber count consistent
  3. To simplify the color coding of conduits
  4. To lower the cost of the conduit

Explanation

Separating communications from power reduces induced interference on metallic members and limits hazards if a fault occurs. Fiber count, color coding, and conduit cost are not the driving reasons for separation.

Question 25Outside Plant Design

In an OSP design, what does a cable assignment or fiber allocation plan primarily document?

  1. The color of the pedestal
  2. The burial depth of each duct segment
  3. Which fibers are assigned to which circuits or customers Correct answer.
  4. The tensile strength of the messenger strand

Explanation

A fiber allocation plan records how individual fibers within cables are assigned to circuits, customers, or spare capacity so records stay accurate through the network's life. Depth, strand strength, and pedestal color are unrelated records.

Question 26Outside Plant Design

Which document symbol set is typically used to show duct bank profiles, manhole locations, and cable routes on OSP construction drawings?

  1. Photographs of the existing utility corridor
  2. A set of standard plan symbols defined in the project legend Correct answer.
  3. A fiber assignment spreadsheet
  4. A bill of materials listing cable quantities

Explanation

Construction drawings rely on a legend that defines each symbol used for ducts, manholes, handholes, poles, and cable routes. The legend is what makes the drawing readable by the contractor, so symbols must be consistent from sheet to sheet. Photographs, material lists, and assignment tables support the design but do not convey geometry.

Question 27Outside Plant Design

What is the standard nominal inside diameter of a typical 1.25-inch trade-size schedule 40 PVC communications duct?

  1. About 1.66 inches Correct answer.
  2. About 1.25 inches
  3. About 2.00 inches
  4. About 1.05 inches

Explanation

Trade size for rigid PVC conduit refers to a nominal designation, not the actual bore. A 1.25-inch trade-size duct has an actual inside diameter of roughly 1.66 inches, which is why designers use actual dimensions when calculating cable fill. Using the trade size directly would understate available capacity.

Question 28Outside Plant Design

In OSP terminology, what distinguishes a manhole from a handhole?

  1. A manhole serves buried cable; a handhole serves only aerial cable
  2. A manhole is always precast concrete; a handhole is always polymer concrete
  3. A manhole is large enough for a worker to enter; a handhole is reached from the surface Correct answer.
  4. A manhole contains splices; a handhole contains only pulling hardware

Explanation

The distinction is based on access, not material or function. A manhole is sized so a technician can enter to work on cable and closures, while a handhole is a smaller structure worked from above grade. Both can contain splices or pulling hardware depending on the design.

Question 29Outside Plant Design

Which condition most strongly justifies specifying aerial rather than buried construction for a new distribution route?

  1. Existing poles are available and the terrain is rocky and costly to excavate Correct answer.
  2. The route passes through a historic district with strict aesthetic rules
  3. The route crosses a navigable waterway
  4. The local jurisdiction requires all new utilities to be underground

Explanation

Aerial construction is usually chosen when usable pole plant already exists and trenching would be expensive, such as in rock. The decision is fundamentally a cost and feasibility comparison between available structures and excavation. Regulatory mandates and waterway crossings push the design in the opposite direction.

Question 30Outside Plant Design

What is the primary purpose of a conduit mandrel and brush operation before pulling cable into a new duct?

  1. To apply lubricant to the cable jacket
  2. To prove the duct is clear and round and to remove debris Correct answer.
  3. To measure the exact length of the duct run
  4. To verify the duct's electrical continuity

Explanation

Mandrelling and brushing confirm that the duct has no obstructions, collapses, or excessive deflection and that it will pass a cable of the intended diameter. It is a proofing step performed before the pull. Length measurement, lubrication, and continuity testing are separate activities.

Question 31Outside Plant Design

Which soil condition presents the greatest risk of wall collapse during open-cut trenching for a duct bank?

  1. Dry compacted clay
  2. Weathered bedrock
  3. Firm glacial till
  4. Loose saturated sand Correct answer.

Explanation

Saturated granular soils have little cohesion and readily slough into an open trench, creating a cave-in hazard. Cohesive clays, bedrock, and till stand better, though all trenches still require protective systems. Soil classification drives shoring and sloping requirements.

Question 32Outside Plant Design

What does a cable route mileage and stationing plan primarily establish for an OSP project?

  1. Distance from a fixed reference point to each structure and feature along the route Correct answer.
  2. The number of strands to assign to each customer
  3. The grounding resistance at each splice point
  4. The optical loss of each fiber in the cable

Explanation

Stationing assigns a running distance from a route origin so that manholes, handholes, poles, and crossings can be located consistently on drawings and in the field. It is a positional reference system, not an optical or electrical measurement. Fiber counts and grounding values are documented elsewhere.

Question 33Outside Plant Design

Which term describes the practice of placing a spare duct alongside active ducts in a new duct bank?

  1. Express conduit provisioning
  2. Innerduct subdivision
  3. Conduit backfilling
  4. Duct redundancy or spare capacity Correct answer.

Explanation

Designers routinely install spare ducts so future cable can be added without new excavation. This spare capacity, sometimes called duct redundancy, avoids the high cost of re-trenching a corridor. It is distinct from innerduct subdivision and from backfilling, which is a construction step.

Question 34Outside Plant Design

A designer must place a new splice point on a 12 km buried route. Which location is generally preferred?

  1. A manhole near the midpoint with vehicle access and room for a closure Correct answer.
  2. A point where the route changes direction sharply in a roadway
  3. A handhole at the lowest elevation on the route
  4. A mid-span location in the duct bank with no structure

Explanation

Splice points belong in accessible structures where crews can set up safely and store the closure and slack. A midpoint manhole with vehicle access meets both requirements. Mid-span splices cannot be serviced, and low, wet locations risk water intrusion.

Question 35Outside Plant Design

A duct run contains two 45-degree bends separated by only 2 m. How should the designer address the resulting cumulative pulling tension?

  1. Add an intermediate pull point or reduce the number of bends Correct answer.
  2. Increase the cable pull speed to reduce friction
  3. Ignore the bends because each is under 90 degrees
  4. Specify a smaller cable to lower the fill ratio

Explanation

Bends close together produce cumulative sidewall pressure and tension that can exceed cable limits. Adding a pull point or revising the alignment to reduce bend count controls the load. Pulling faster increases tension, and smaller cable does not solve the geometric problem.

Question 36Outside Plant Design

A route must cross a four-lane highway with heavy traffic that cannot be interrupted. Which construction method is best suited?

  1. Directional boring beneath the roadway Correct answer.
  2. Shallow plowing along the shoulder
  3. Open-cut trenching with flaggers
  4. Aerial attachment to existing poles

Explanation

Trenchless methods such as directional boring install duct beneath a roadway without cutting pavement or stopping traffic. Open cutting and plowing both disrupt the surface and traffic. Aerial attachment requires suitable poles and clearances that may not exist at the crossing.

Question 37Outside Plant Design

What is the purpose of a conduit end plug or duct seal at a building entrance?

  1. To identify the duct with a color code
  2. To prevent water, gas, and rodents from entering through the duct Correct answer.
  3. To anchor the cable against pulling tension
  4. To provide grounding continuity for the cable shield

Explanation

Duct seals block the pathway between the outside plant and the building interior, keeping out water, sewer gas, and pests. Cable anchoring and bonding are handled by separate hardware. Identification is done with markers and labels.

Question 38Outside Plant Design

When computing the fill ratio for a duct containing multiple cables, which value is compared?

  1. Cable bend radius to duct length
  2. Total cable cross-sectional area to the duct inside cross-sectional area Correct answer.
  3. Cable weight to duct weight
  4. Number of fibers to duct diameter

Explanation

Fill ratio is the ratio of the summed cable cross-sectional areas to the internal area of the duct. It predicts whether cables can be pulled without excessive friction or jamming. Weight, fiber count, and bend radius are separate design considerations.

Question 39Outside Plant Design

A designer is laying out an aerial route along a pole line and must account for the sag of a new span. Which factor most directly increases sag for a given span length?

  1. Increased pole height
  2. Use of a larger messenger strand
  3. Lower cable weight and lower temperature
  4. Higher conductor or cable weight and higher temperature Correct answer.

Explanation

Sag increases with the weight per unit length of the cable and with thermal expansion as temperature rises. Heavier cable and higher temperature both lower the tension available to hold the span up. Pole height and messenger size change geometry and strength but do not by themselves increase sag.

Question 40Outside Plant Design

A designer needs to verify that a proposed duct bank has adequate cover beneath a residential street. Which factor governs the minimum depth?

  1. The color of the duct
  2. The owner's preference alone
  3. The number of spare ducts installed
  4. Local code, roadway loading, and frost penetration Correct answer.

Explanation

Minimum cover is set by the governing code and must account for traffic loading on the roadway and frost depth in the region. Both factors protect the duct from damage and heaving. Duct color and spare capacity do not determine burial depth.

Question 41Outside Plant Design

What is the main reason for specifying a concrete encasement around a duct bank under a railroad crossing?

  1. To reduce the cost of excavation
  2. To improve the duct's optical performance
  3. To distribute load and protect ducts from heavy dynamic loading Correct answer.
  4. To provide a path for grounding conductors

Explanation

Concrete encasement spreads concentrated rail and traffic loads over the duct bank and shields ducts from impact and settlement. It has no effect on optical transmission. Encasement adds cost and is not used for grounding.

Question 42Outside Plant Design

A designer is choosing between a 24-fiber and a 48-fiber cable for a new feeder route with uncertain future demand. Which consideration most supports the larger count?

  1. Higher fiber counts eliminate the need for splice closures
  2. The cost of recabling a buried route later is far higher than the incremental cable cost now Correct answer.
  3. Larger cables always have lower attenuation
  4. Larger cables reduce the required duct diameter

Explanation

Because buried plant is expensive to reopen, designers often install spare fibers up front to avoid future construction. The incremental cost of a larger cable is small compared with re-trenching. Fiber count does not improve attenuation, remove closures, or shrink duct size.

Question 43Outside Plant Design

What does a route survey typically document that a desktop design cannot reliably establish?

  1. The exact attenuation of each fiber span
  2. The final splice loss values
  3. Field conditions such as obstructions, utilities, and access constraints Correct answer.
  4. The customer's service activation date

Explanation

A field survey captures what maps miss: existing utilities, obstructions, terrain, access, and environmental constraints that shape the route. Attenuation and splice loss are measured after installation. Activation dates are commercial, not survey, data.

Question 44Outside Plant Design

A designer is evaluating a duct bank that will pass under a paved parking lot subject to heavy truck traffic. Which design change best addresses the added load?

  1. Remove the spare ducts
  2. Increase cover depth or add encasement over the ducts Correct answer.
  3. Switch to a smaller duct trade size
  4. Reduce the number of ducts in the bank

Explanation

Heavy wheel loads are managed by increasing the depth of cover and by encasing or otherwise strengthening the duct bank. Reducing duct count, shrinking ducts, or removing spares changes capacity and does not address structural loading.

Question 45Outside Plant Design

Which factor most directly determines the required number of handholes along a buried drop route serving individual premises?

  1. The color of the drop cable jacket
  2. The maximum distance a crew can conveniently pull or rod between access points Correct answer.
  3. The number of fibers in the feeder cable
  4. The height of nearby poles

Explanation

Handhole spacing is driven by practical limits on pulling, rodding, and accessing cable, along with the need to serve individual premises. Feeder fiber count and jacket color do not set access spacing. Pole height is relevant only to aerial plant.

Question 46Outside Plant Design

A route traverses a region with seasonal frost penetration to 1.2 m. What design implication should the designer apply to buried duct?

  1. Reduce duct cover to save excavation cost
  2. Use only aerial construction in that region
  3. Place duct below the frost line or use measures that resist frost heave Correct answer.
  4. Eliminate expansion provisions from the design

Explanation

Frost heave can lift and deform shallow duct, so duct is placed below the frost line where practical or protected with suitable backfill and detailing. Reducing cover increases the risk. Aerial construction is a separate decision, and expansion provisions remain important.

Question 47Outside Plant Design

A designer is comparing two duct bank alignments: one is 300 m shorter but passes through an area where two undocumented utility lines are suspected. What is the most defensible design action?

  1. Assume the suspected utilities are abandoned
  2. Perform utility locating and potholing before committing to the alignment Correct answer.
  3. Choose the longer route without evaluating either option
  4. Select the shorter route and proceed without further investigation

Explanation

Undocumented utilities are a major risk to both safety and schedule, so they must be located and confirmed by potholing before the alignment is fixed. Proceeding on assumption or abandoning the shorter route without data are both unsupported. The investigation provides the basis for a sound comparison.

Question 48Outside Plant Design

A long duct run will be installed in a corridor where the water table lies above the proposed duct elevation. Which combination of measures best protects the installation?

  1. Shallow cover to raise the duct above the water table
  2. Open joints to allow pressure equalization
  3. Removal of all spare ducts to reduce buoyancy
  4. Watertight duct joints and seals plus a drainage or dewatering strategy Correct answer.

Explanation

Duct below the water table must be kept dry through sealed joints and watertight structures, supported by drainage or dewatering so the duct bank is not subjected to hydrostatic pressure or buoyancy. Open joints admit water, and shallow cover may not clear the water table.

Question 49Outside Plant Design

A designer must place a splice closure in a duct bank that passes through a flood-prone area. Which approach best balances accessibility and reliability?

  1. Place the closure in the lowest manhole to shorten cable runs
  2. Seal the manhole and accept periodic flooding of the closure
  3. Raise the splice structure above the flood level or relocate the splice to a drier structure Correct answer.
  4. Eliminate the splice and exceed the maximum cable length

Explanation

Splice closures should be located where they remain dry and accessible, so raising the structure or relocating the splice is the preferred response. Accepting flooding risks water intrusion and corrosion. Eliminating a splice may violate length and loss limits.

Question 50Outside Plant Design

An aerial route must cross a navigable waterway, and the permitting authority sets a minimum clearance above high water. Which design action most directly ensures compliance?

  1. Use a smaller cable to reduce span weight
  2. Lower the attachment height to reduce wind loading
  3. Add more poles to shorten spans without checking clearance
  4. Increase messenger tension to reduce sag and verify clearance at the governing temperature Correct answer.

Explanation

Clearance over navigable water is governed by sag under the worst-case temperature and loading, so tension and sag must be calculated and verified against the permit condition. Adding poles or reducing weight may help but must be evaluated against the clearance requirement. Lowering attachment height reduces clearance.