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Punjab PSEB Matric NSQF Telecom (Optical Fiber Splicer) study materials
Punjab PSEB Matric NSQF Telecom (Optical Fiber Splicer) study resources

Punjab PSEB Matric NSQF Telecom (Optical Fiber Splicer) practice questions

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Question 1Optical Fiber Fundamentals and Transmission Principles

A telecom technician is explaining the structure of a standard single-mode optical fiber to a trainee. Which layer carries the majority of the transmitted optical signal?

  1. The outer protective jacket
  2. The cladding
  3. The core Correct answer.
  4. The aramid strength yarn

Explanation

In an optical fiber the light signal is guided mainly inside the core, which has a slightly higher refractive index than the surrounding cladding. The cladding confines the light by total internal reflection, while the jacket and strength yarn provide only mechanical and environmental protection.

Question 2Optical Fiber Fundamentals and Transmission Principles

Light stays inside the core of an optical fiber because of which physical principle?

  1. Absorption of light by the cladding
  2. Total internal reflection at the core-cladding boundary Correct answer.
  3. Diffraction through the protective jacket
  4. Refraction of light into the outer coating

Explanation

When light travelling in the higher-index core strikes the core-cladding boundary at an angle greater than the critical angle, it is reflected back into the core rather than refracted out. This total internal reflection is the guiding mechanism in all conventional glass optical fibers.

Question 3Optical Fiber Fundamentals and Transmission Principles

Which wavelength window is most commonly used for long-haul single-mode optical fiber transmission because of its lowest attenuation?

  1. 1310 nm
  2. 850 nm
  3. 650 nm
  4. 1550 nm Correct answer.

Explanation

Silica fiber reaches its minimum attenuation, roughly 0.2 dB per kilometre, near 1550 nm, which is why this window is standard for long-haul and DWDM systems. The 1310 nm window has zero chromatic dispersion but higher loss, and 850 nm is used mainly in short multimode links.

Question 4Optical Fiber Fundamentals and Transmission Principles

A splicer is working with a fiber whose core diameter is about 9 micrometres and which supports only one propagation mode. What type of fiber is this?

  1. Step-index multimode fiber
  2. Graded-index multimode fiber
  3. Single-mode fiber Correct answer.
  4. Plastic optical fiber

Explanation

A core of about 8 to 10 micrometres supports a single propagation mode at telecom wavelengths and is therefore called single-mode fiber. Multimode fibers have much larger cores, typically 50 or 62.5 micrometres, that allow many modes to travel.

Question 5Optical Fiber Fundamentals and Transmission Principles

Which unit is used to express optical power loss along a fiber span?

  1. Micrometre (µm)
  2. Decibel (dB) Correct answer.
  3. Ohm (Ω)
  4. Nanometre (nm)

Explanation

Loss in fiber links is expressed in decibels, calculated as ten times the logarithm of the input-to-output power ratio. Nanometres and micrometres describe wavelength and dimensions, while ohms measure electrical resistance.

Question 6Optical Fiber Fundamentals and Transmission Principles

Why are single-mode fibers generally preferred over multimode fibers for links spanning tens of kilometres?

  1. They can be terminated with cheaper plastic connectors
  2. They transmit visible light more efficiently
  3. They have a larger core that captures more light
  4. They avoid modal dispersion and have lower attenuation Correct answer.

Explanation

Because only one mode propagates, single-mode fiber suffers no modal dispersion, so pulses stay sharp over long distances. It also operates in the low-loss 1310 and 1550 nm windows, making it the standard choice for long-haul routes.

Question 7Optical Fiber Fundamentals and Transmission Principles

What does the numerical aperture (NA) of an optical fiber describe?

  1. The maximum tensile load the cable can bear
  2. The colour of the fiber jacket
  3. The range of angles over which the fiber accepts incoming light Correct answer.
  4. The number of splices allowed per kilometre

Explanation

Numerical aperture indicates the light-gathering ability of the fiber, that is, the cone of angles within which incoming rays will be guided. A larger NA accepts light over a wider angle, which matters for launch efficiency and splice tolerance.

Question 8Optical Fiber Fundamentals and Transmission Principles

A fiber span has 0.4 dB/km attenuation and is 12 km long. Ignoring splice and connector losses, what is the total fiber attenuation?

  1. 3.0 dB
  2. 12.0 dB
  3. 4.8 dB Correct answer.
  4. 0.48 dB

Explanation

Total attenuation equals the loss per kilometre multiplied by the length, so 0.4 dB/km times 12 km gives 4.8 dB. This value would then be added to splice and connector losses to obtain the total link budget.

Question 9Optical Fiber Fundamentals and Transmission Principles

In a graded-index multimode fiber, what is the main purpose of gradually changing the refractive index across the core?

  1. To allow the fiber to carry electrical current
  2. To increase the total attenuation of the fiber
  3. To make the cladding unnecessary
  4. To reduce modal dispersion by equalising path delays Correct answer.

Explanation

In a graded-index core, rays travelling away from the axis follow curved paths through lower-index glass and arrive at nearly the same time as axial rays. This equalisation of propagation delays greatly reduces modal dispersion compared with a step-index multimode fiber.

Question 10Optical Fiber Fundamentals and Transmission Principles

A technician measures 1 mW at the input of a fiber link and 0.1 mW at the output. What is the loss in decibels?

  1. 1 dB
  2. 20 dB
  3. 10 dB Correct answer.
  4. 0.1 dB

Explanation

Loss in decibels is ten times the base-10 logarithm of the power ratio, so 10 × log10(1/0.1) equals 10 dB. A tenfold reduction in power always corresponds to 10 dB of loss.

Question 11Optical Fiber Fundamentals and Transmission Principles

Which phenomenon causes different spectral components of a signal to travel at different speeds in a single-mode fiber, broadening the pulse?

  1. Connector misalignment
  2. Chromatic dispersion Correct answer.
  3. Macrobending loss
  4. Polarisation-dependent loss

Explanation

Chromatic dispersion arises because the refractive index of silica varies with wavelength, so different spectral parts of a modulated signal propagate at different velocities. The resulting pulse broadening limits bit rate over long single-mode spans and can be managed with dispersion-compensating modules.

Question 12Optical Fiber Fundamentals and Transmission Principles

A fusion splicer shows a high splice loss on a single-mode fiber. Which condition most directly explains this result?

  1. A large core offset or angular misalignment between the two fiber ends Correct answer.
  2. The fiber jacket is coloured yellow
  3. The OTDR was set to a long pulse width
  4. The splice protector sleeve is transparent

Explanation

In single-mode fiber the core is only about 9 micrometres wide, so lateral offset or angular misalignment between the two cleaved ends throws light into the cladding and raises splice loss. Good cleave quality and accurate alignment are therefore essential.

Question 13Optical Fiber Fundamentals and Transmission Principles

Why must the two fibers joined by fusion splicing belong to the same type, for example both standard single-mode?

  1. Because fusion splicers cannot heat two different glasses
  2. Because mismatched mode field diameters cause additional splice loss Correct answer.
  3. Because different jacket colours cannot be stripped
  4. Because the splice protector will not fit

Explanation

Joining fibers with different mode field diameters, such as single-mode to multimode, creates a discontinuity at which part of the light is lost. Matching fiber types keeps the mode field and numerical aperture consistent and minimises splice loss.

Question 14Optical Fiber Fundamentals and Transmission Principles

A link budget allows 20 dB total loss. The fiber contributes 12 dB, connectors contribute 2 dB, and there will be four splices. What maximum average splice loss can be tolerated?

  1. 1.5 dB per splice Correct answer.
  2. 0.5 dB per splice
  3. 6.0 dB per splice
  4. 2.0 dB per splice

Explanation

Subtracting fiber and connector losses from the budget leaves 20 − 12 − 2 = 6 dB for all four splices. Dividing 6 dB by four splices gives a maximum average of 1.5 dB per splice.

Question 15Optical Fiber Fundamentals and Transmission Principles

What is the primary function of the cladding in a single-mode optical fiber?

  1. To supply mechanical strength to the cable
  2. To block ultraviolet radiation from sunlight
  3. To confine light in the core by total internal reflection Correct answer.
  4. To carry the optical signal to the receiver

Explanation

The cladding has a slightly lower refractive index than the core, creating the boundary at which total internal reflection occurs and keeping the guided light inside the core. Mechanical strength is provided by the coating, strength members and jacket, not by the cladding.

Question 16Optical Fiber Fundamentals and Transmission Principles

A fiber is bent into a tight coil with a radius smaller than the recommended minimum. What effect should the technician expect?

  1. A decrease in numerical aperture along the whole span
  2. Increased loss caused by light escaping at the bend Correct answer.
  3. A permanent change in the transmission wavelength
  4. An increase in the signal power at the far end

Explanation

Bending a fiber beyond its minimum bend radius allows guided light to radiate out of the core, producing macrobending loss. This loss is why installation practices specify minimum bend radii and why bend-insensitive fibers are used in crowded enclosures.

Question 17Optical Fiber Fundamentals and Transmission Principles

Which statement correctly compares attenuation at 1310 nm and 1550 nm in standard single-mode fiber?

  1. Attenuation is identical at both wavelengths
  2. Attenuation is lower at 1550 nm than at 1310 nm Correct answer.
  3. Attenuation at 1550 nm is zero
  4. Attenuation is lower at 1310 nm than at 1550 nm

Explanation

Standard silica single-mode fiber has attenuation of roughly 0.35 dB/km at 1310 nm and about 0.2 dB/km at 1550 nm, so loss is lower in the longer-wavelength window. The 1310 nm window is nevertheless used where zero chromatic dispersion is more important than minimum loss.

Question 18Optical Fiber Fundamentals and Transmission Principles

Why is 1310 nm sometimes chosen for short and medium single-mode links even though 1550 nm has lower loss?

  1. Because 1310 nm lasers are always cheaper than any other type
  2. Because chromatic dispersion is near zero around 1310 nm in standard fiber Correct answer.
  3. Because 1310 nm is the only window supported by single-mode fiber
  4. Because 1310 nm light cannot be attenuated by splices

Explanation

In standard single-mode fiber the zero-dispersion wavelength lies close to 1310 nm, so pulses broaden very little from chromatic dispersion at that window. On shorter links the slightly higher attenuation matters less than the dispersion benefit.

Question 19Optical Fiber Fundamentals and Transmission Principles

Which factor primarily limits the maximum transmission distance of a multimode fiber link?

  1. The colour of the connector housing
  2. The length of the fiber jacket
  3. Modal dispersion spreading the pulses Correct answer.
  4. The number of fusion splices in the patch panel

Explanation

In multimode fiber, different modes travel different path lengths and arrive at different times, so pulses spread and eventually overlap. This modal dispersion limits both the bit rate and the reach, which is why multimode is used mainly in buildings and data centres.

Question 20Optical Fiber Fundamentals and Transmission Principles

An OTDR trace shows a sudden step increase in loss at a point along a single-mode span, with no reflective spike. What does this most likely indicate?

  1. A change of connector polish at the OTDR port
  2. A transmitter wavelength drift
  3. A mechanical splice or fusion splice with excess loss Correct answer.
  4. A break at the far end of the fiber

Explanation

A non-reflective step in the OTDR trace is characteristic of a splice whose loss exceeds expectations, since fusion and mechanical splices generally produce little or no reflection. A reflective spike would instead suggest a connector or an air gap.

Question 21Optical Fiber Fundamentals and Transmission Principles

A single-mode link must carry 10 Gbps over 80 km without regeneration. Which combination of measures is most appropriate?

  1. Use graded-index multimode fiber with a short pulse width
  2. Use 650 nm visible sources with step-index fiber
  3. Use 850 nm multimode fiber with plastic connectors
  4. Use 1550 nm single-mode fiber with dispersion compensation and adequate optical power budget Correct answer.

Explanation

Long high-bit-rate spans need the low attenuation of the 1550 nm window together with management of chromatic dispersion and a sufficient optical power budget. Multimode or visible-wavelength options cannot support such distance and bit rate.

Question 22Optical Fiber Fundamentals and Transmission Principles

Two single-mode fibers are fusion spliced with a small lateral core offset. Which statement best explains the resulting loss?

  1. The splice protector absorbs the light
  2. Part of the mode field fails to couple into the receiving core and radiates into the cladding Correct answer.
  3. The offset changes the transmitter wavelength
  4. The offset increases the numerical aperture of both fibers

Explanation

The guided mode field extends slightly beyond the core, so a lateral offset means the two mode fields overlap imperfectly. The non-overlapping portion couples into cladding modes and is lost, which is why alignment accuracy dominates single-mode splice quality.

Question 23Optical Fiber Fundamentals and Transmission Principles

A technician measures a total link loss of 18 dB against a budget of 22 dB, but the receiver still reports errors at high bit rate. Which explanation is most consistent with these readings?

  1. The fiber jacket is the wrong colour
  2. The link has excessive attenuation and needs more amplifiers
  3. The OTDR was calibrated in the wrong units
  4. Dispersion is broadening the pulses even though the power budget is met Correct answer.

Explanation

Meeting the power budget only guarantees adequate received power; it does not guarantee pulse shape. Chromatic or polarisation-mode dispersion can spread pulses until they overlap, producing errors even when loss is within specification.

Question 24Optical Fiber Fundamentals and Transmission Principles

Why does a fusion splice generally exhibit lower loss and greater long-term reliability than a mechanical splice in a single-mode network?

  1. Mechanical splices always use multimode fiber
  2. Mechanical splices cannot be protected from moisture
  3. The fusion process creates a continuous glass joint with no air gap or index-matching gel Correct answer.
  4. Fusion splices are always shorter in physical length

Explanation

Fusion splicing melts the two cleaved ends into a continuous glass joint, eliminating the air gap and the need for index-matching gel that can degrade over time. Mechanical splices rely on gel and alignment hardware, so they typically show slightly higher loss and long-term drift.

Question 25Fiber Optic Cable Types, Construction and Colour Coding

In a standard 12-fibre colour code, which colour identifies fibre number 4?

  1. Slate
  2. Green
  3. Yellow Correct answer.
  4. Brown

Explanation

The 12-fibre sequence runs blue, orange, green, brown, slate, white, red, black, yellow, violet, rose and aqua. Position 4 is therefore brown, and yellow only appears at position 9 in the group of twelve.

Question 26Fiber Optic Cable Types, Construction and Colour Coding

A loose-tube cable carries 48 fibres. Using the standard colour code with binder colours, how is fibre 13 identified?

  1. Blue fibre in an orange binder Correct answer.
  2. Orange fibre in a blue binder
  3. Blue fibre in a green binder
  4. Blue fibre in a blue binder

Explanation

Fibres are counted in groups of twelve, so fibre 13 is the first fibre of the second group. The first group uses the blue binder and the second group uses the orange binder, so fibre 13 is a blue fibre inside an orange binder.

Question 27Fiber Optic Cable Types, Construction and Colour Coding

In a ribbon cable the ribbons themselves are colour coded with the same twelve-colour sequence. What does a black ribbon indicate?

  1. Ribbon number 8 Correct answer.
  2. Ribbon number 6
  3. Ribbon number 7
  4. Ribbon number 12

Explanation

Ribbon identification follows the same twelve-colour order used for fibres: blue, orange, green, brown, slate, white, red, black, yellow, violet, rose, aqua. Black is the eighth colour in that order, so a black ribbon is ribbon 8.

Question 28Fiber Optic Cable Types, Construction and Colour Coding

Which statement correctly describes the construction of a tight-buffered distribution fibre cable?

  1. Bare 250 micrometre fibres float freely inside a water-blocked gel-filled tube
  2. Fibres are enclosed in a corrugated steel armour with no strength members
  3. Each fibre has a 900 micrometre buffer directly bonded to the coating and is reinforced with aramid yarn Correct answer.
  4. A single 900 micrometre buffer surrounds a bundle of twelve bare fibres

Explanation

In a tight-buffered distribution cable every fibre is individually coated with a 900 micrometre buffer that is in direct contact with the fibre coating. Aramid yarn provides tensile strength and the outer sheath protects the assembly, which suits indoor riser and patch applications.

Question 29Fiber Optic Cable Types, Construction and Colour Coding

Which cable type is best suited for direct burial along a roadside in Punjab without additional ducting?

  1. Loose-tube armoured cable with a moisture barrier Correct answer.
  2. Simplex indoor patch cord
  3. Riser-rated tight-buffered cable
  4. Aerial figure-eight cable without messenger

Explanation

Direct burial demands mechanical protection against soil pressure, rodent attack and moisture ingress. A loose-tube armoured cable with a moisture barrier and a PE outer sheath is designed for this environment, whereas indoor and aerial designs are not.

Question 30Fiber Optic Cable Types, Construction and Colour Coding

What is the primary purpose of the central strength member in a loose-tube optical fibre cable?

  1. To block water from entering the tube
  2. To carry the optical signal between tubes
  3. To provide electrical earthing for the cable
  4. To limit strain on the fibres during installation and temperature cycling Correct answer.

Explanation

The central strength member, usually a steel wire or FRP rod, takes up the tensile load applied during pulling and limits contraction and expansion of the cable with temperature. This keeps the fibres within their allowable strain limits.

Question 31Fiber Optic Cable Types, Construction and Colour Coding

Which colour code applies to the tubes of a multi-tube loose-tube cable when the cable contains more than twelve tubes?

  1. Tubes are identified by their position only, since colour coding stops at twelve
  2. Tubes repeat the twelve-colour sequence and are grouped by coloured binder threads or wrap Correct answer.
  3. Tubes use a black and white stripe pattern with no standard order
  4. Tubes are all natural colour and identified only by printed numbers

Explanation

When more than twelve tubes are present, the twelve-colour sequence repeats and each group of twelve is marked with a coloured binder thread or wrap. This allows a splicer to identify any tube unambiguously in a large cable.

Question 32Fiber Optic Cable Types, Construction and Colour Coding

A single-mode cable is marked with a yellow outer sheath. What does this colour conventionally indicate?

  1. Single-mode fibre Correct answer.
  2. Multimode 62.5/125 fibre
  3. Armoured outdoor construction
  4. Halogen-free flame-retardant sheath

Explanation

In common industry practice a yellow sheath signals single-mode fibre, while orange is widely used for multimode. The colour is a quick visual guide and should still be confirmed against the cable print legend.

Question 33Fiber Optic Cable Types, Construction and Colour Coding

In a 24-fibre cable using the twelve-colour code with blue and orange binders, which fibre is the last one of the orange group?

  1. Rose fibre in the orange binder
  2. Aqua fibre in the orange binder Correct answer.
  3. Violet fibre in the blue binder
  4. Aqua fibre in the blue binder

Explanation

The orange binder holds fibres 13 to 24, and the last fibre of any twelve-fibre group is aqua. Therefore the final fibre of the orange group is an aqua fibre inside the orange binder.

Question 34Fiber Optic Cable Types, Construction and Colour Coding

Why is a gel-filled loose tube used in outdoor optical fibre cables?

  1. To allow the fibres to be spliced without stripping the coating
  2. To prevent water ingress and protect the fibre from moisture-driven degradation Correct answer.
  3. To increase the optical power launched into the fibre
  4. To reduce the weight of the cable during pulling

Explanation

The thixotropic gel fills the free space in the tube so that water cannot travel along the cable. This prevents fibre degradation from moisture and protects against freeze-thaw damage in outdoor environments.

Question 35Fiber Optic Cable Types, Construction and Colour Coding

A figure-eight aerial cable is being installed between poles. What is the function of the messenger wire in this construction?

  1. It acts as a water-blocking element inside the fibre tube
  2. It supplies power to the optical network unit
  3. It carries the tensile load so the fibre unit remains strain free Correct answer.
  4. It provides the optical return path for bidirectional transmission

Explanation

In a figure-eight cable the messenger is a separate steel strand joined to the fibre unit by a web. The messenger supports the span and carries the tension, keeping the optical fibres free from strain.

Question 36Fiber Optic Cable Types, Construction and Colour Coding

Which fibre core and cladding dimensions correspond to standard multimode fibre used in short-reach LAN backbones?

  1. 9/125 micrometres
  2. 50/125 micrometres only
  3. 8/125 micrometres
  4. 62.5/125 micrometres Correct answer.

Explanation

62.5/125 micrometre multimode fibre has a 62.5 micrometre core and a 125 micrometre cladding, a widely installed standard for short-reach LAN backbones. The 125 micrometre cladding is common to standard single-mode and multimode fibres.

Question 37Fiber Optic Cable Types, Construction and Colour Coding

A loose-tube cable has a dry water-blocking design using superabsorbent powder instead of gel. What is the main practical advantage for a splicer?

  1. The cable no longer requires a strength member
  2. The fibres no longer need fusion splicing
  3. Tube access is cleaner and faster because there is no gel to remove Correct answer.
  4. The cable can be spliced without any cleaning of the fibres

Explanation

Dry water-blocking cables use swelling powder or tapes rather than gel, so tubes can be opened and fibres cleaned quickly without solvent. This speeds up preparation and reduces contamination risk at the splice point.

Question 38Fiber Optic Cable Types, Construction and Colour Coding

In a 12-fibre colour code, which colour appears immediately after slate?

  1. Violet
  2. Rose
  3. White Correct answer.
  4. Brown

Explanation

The sequence is blue, orange, green, brown, slate, white, red, black, yellow, violet, rose, aqua. Slate is fifth and white is sixth, so white follows slate directly.

Question 39Fiber Optic Cable Types, Construction and Colour Coding

A cable print legend reads 'SM 9/125 G.652.D, LSZH, 24F'. Which two properties are confirmed by this legend?

  1. Single-mode fibre with steel wire armour
  2. Multimode fibre with a gel-filled tube
  3. Multimode fibre with a polyethylene sheath
  4. Single-mode fibre with a low-smoke zero-halogen sheath Correct answer.

Explanation

SM 9/125 identifies single-mode fibre with a 9 micrometre core and 125 micrometre cladding, and G.652.D is a standard single-mode specification. LSZH confirms a low-smoke zero-halogen sheath, which matters for indoor fire safety.

Question 40Fiber Optic Cable Types, Construction and Colour Coding

Which colour sequence correctly lists fibres 9 to 12 of a standard twelve-fibre group?

  1. Rose, aqua, yellow, violet
  2. Yellow, violet, rose, aqua Correct answer.
  3. Aqua, yellow, violet, rose
  4. Violet, rose, aqua, yellow

Explanation

Counting the twelve-colour order, position 9 is yellow, 10 is violet, 11 is rose and 12 is aqua. So fibres 9 to 12 read yellow, violet, rose, aqua in that order.

Question 41Fiber Optic Cable Types, Construction and Colour Coding

Why are aramid yarns included in an indoor tight-buffered breakout cable?

  1. To act as a water-blocking layer in the tube
  2. To conduct heat away from the fibres
  3. To increase the numerical aperture of the fibre
  4. To provide tensile strength while remaining non-conductive Correct answer.

Explanation

Aramid yarn is a high-strength, non-conductive fibre that carries pulling tension in indoor cables. Being dielectric, it avoids metallic conduction paths and suits riser and equipment-room installations.

Question 42Fiber Optic Cable Types, Construction and Colour Coding

A technician must identify fibre 25 in a 36-fibre loose-tube cable. Which combination of colours should be expected?

  1. Green fibre in a blue binder
  2. Blue fibre in a brown binder
  3. Green fibre in a brown binder
  4. Blue fibre in a green binder Correct answer.

Explanation

Fibres are counted in groups of twelve: 1 to 12 in the blue binder, 13 to 24 in the orange binder and 25 to 36 in the green binder. Fibre 25 is the first fibre of the third group, so it is a blue fibre inside a green binder.

Question 43Fiber Optic Cable Types, Construction and Colour Coding

An outdoor duct cable and an indoor riser cable are compared. Which pair of features correctly distinguishes them?

  1. Duct cable: aramid yarn only; riser cable: steel armour only
  2. Duct cable: tight-buffered fibres and LSZH sheath; riser cable: gel-filled loose tubes and PE sheath
  3. Duct cable: gel-filled loose tubes and PE sheath; riser cable: tight-buffered fibres and flame-retardant sheath Correct answer.
  4. Duct cable: aqua sheath; riser cable: yellow sheath

Explanation

Outdoor duct cables use gel-filled loose tubes with a polyethylene sheath for moisture and UV protection. Indoor riser cables use tight-buffered fibres with a flame-retardant sheath to meet fire-safety requirements in buildings.

Question 44Fiber Optic Cable Types, Construction and Colour Coding

A 12-fibre group is described as using the colour code with a black fibre present. Which position does the black fibre occupy?

  1. Position 9
  2. Position 7
  3. Position 8 Correct answer.
  4. Position 6

Explanation

In the twelve-colour sequence blue, orange, green, brown, slate, white, red, black, yellow, violet, rose, aqua, black is the eighth colour. It therefore marks position 8 in the group.

Question 45Tools, Equipment and Safety in Fiber Splicing Work

While preparing an optical fiber splicing site, which personal protective equipment is most important for protecting the eyes from glass shards and chemical splashes?

  1. Steel-toe safety shoes
  2. Cotton hand gloves
  3. Safety goggles with side shields Correct answer.
  4. Ear plugs

Explanation

Cleaved fiber ends and chemicals such as alcohol or index-matching gel can injure the eyes, so close-fitting safety goggles with side shields are the standard eye protection at a splicing bench. Other items protect hands, feet or hearing but do not guard the eyes.

Question 46Tools, Equipment and Safety in Fiber Splicing Work

A splicer needs to remove the 250 micrometre primary coating from a single-mode fiber before cleaning and cleaving. Which tool is designed specifically for this step?

  1. Optical time domain reflectometer
  2. Visual fault locator
  3. Miller stripping tool with a 250 micron hole Correct answer.
  4. Fusion splicer electrode

Explanation

A Miller-style stripping tool has sized holes matched to the fiber coating diameter, and the 250 micron hole grips the primary coating so it can be pulled off without nicking the glass. The other devices perform splicing, testing or fault location, not coating removal.

Question 47Tools, Equipment and Safety in Fiber Splicing Work

Before making a splice, a technician wipes a stripped fiber with a lint-free tissue moistened with isopropyl alcohol. What is the main purpose of this action?

  1. To remove coating residue and dust that would cause bubbles or high loss Correct answer.
  2. To soften the glass so it cleaves more easily
  3. To make the fiber fluorescent under the splicer camera
  4. To increase the refractive index of the cladding

Explanation

Cleaning removes residual coating, dust and skin oils that would otherwise burn inside the arc and create bubbles, voids or high splice loss. Alcohol does not soften glass, change the cladding index or add fluorescence.

Question 48Tools, Equipment and Safety in Fiber Splicing Work

After cleaving, a technician must place a fiber end into the splicer. Which practice best protects the eyes and fingers from a sharp fiber end?

  1. Carry the fiber close to the face to see the end clearly
  2. Wipe the offcut onto the floor with a cloth
  3. Keep the cleaved end pointed away and dispose of offcuts in a sealed sharps container Correct answer.
  4. Blow the offcut away with compressed air

Explanation

Cleaved fiber ends are extremely sharp and can penetrate skin or eye tissue, so ends should be pointed away from the body and offcuts placed in a closed sharps container. Blowing or wiping offcuts spreads invisible glass fragments into the workspace.

Question 49Tools, Equipment and Safety in Fiber Splicing Work

Which instrument is used to check the quality of a completed splice by measuring splice loss and reflecting events along the fiber link?

  1. Fiber cleaver
  2. Heat shrink oven
  3. Fusion splicer
  4. Optical time domain reflectometer Correct answer.

Explanation

An optical time domain reflectometer sends light pulses and analyses backscatter and reflections to report splice loss and event distance. Cleavers, ovens and splicers prepare or join fibers but do not measure link loss.

Question 50Tools, Equipment and Safety in Fiber Splicing Work

Why must the fusion splicer be placed on a stable, level workbench with the wind cover closed during arc fusion?

  1. To stop the fiber from being cleaned by the arc
  2. To prevent air currents from disturbing the arc and causing uneven heating Correct answer.
  3. To reduce the brightness of the viewing screen
  4. To keep the electrodes cool between splices

Explanation

Drafts can bend or cool the arc unevenly, producing weak or offset splices, so the wind cover and a stable bench protect arc stability. The cover is not a cooling device, does not prevent cleaning and is unrelated to screen brightness.