I85PREP
⌘ K
Odisha CHSE +2 Plumber General (VOC-ITV) study materials
Odisha CHSE +2 Plumber General (VOC-ITV) study resources

Odisha CHSE +2 Plumber General (VOC-ITV) practice questions

One question at a time. Build your Odisha CHSE +2 Plumber General (VOC-ITV) understanding.

First 50 of 200 questions. Each one lists the choices, the correct answer, and an explanation. The checker at the top of this page saves progress in this browser when it is available.

Continue in the practice tool above to load more questions, 50 at a time.

Question 1Plumbing Tools, Materials and Safety Practices

Which plumbing hand tool is designed to cut external threads on GI pipe ends so that fittings can be screwed on?

  1. Caulking iron
  2. Tube cutter
  3. Pipe die and stock Correct answer.
  4. Flaring tool

Explanation

A pipe die held in a stock (die stock) cuts external threads on the outside of a GI or MS pipe so that sockets, elbows and other threaded fittings can be screwed onto it. Threads are cut progressively with cutting oil and the die reversed slightly to break chips.

Question 2Plumbing Tools, Materials and Safety Practices

A plumber must cut a 25 mm diameter GI pipe squarely in a confined space using only hand tools. Which tool is most appropriate?

  1. Cold chisel and hammer
  2. Hacksaw with a fine-tooth blade Correct answer.
  3. Wood rasp
  4. Tenon saw

Explanation

A hacksaw fitted with a fine-tooth blade (about 18 to 24 teeth per inch) cuts metal pipe squarely and cleanly with a narrow kerf, which suits confined spaces. The cut end is then filed and reamed before threading.

Question 3Plumbing Tools, Materials and Safety Practices

What is the primary purpose of applying cutting oil while threading a GI pipe with a die?

  1. To soften the pipe so the die cuts faster
  2. To make the thread permanently rust-proof
  3. To cool the die and flush away metal chips Correct answer.
  4. To increase the pipe diameter slightly

Explanation

Cutting oil lubricates the die faces, carries away heat and flushes chips out of the thread being formed. This gives cleaner threads and longer die life. It is not a permanent protective coating.

Question 4Plumbing Tools, Materials and Safety Practices

Which material is commonly used for soil and waste pipes because it is light, corrosion-resistant and joined by solvent cement?

  1. Cast iron
  2. Galvanised steel
  3. Asbestos cement
  4. PVC Correct answer.

Explanation

Unplasticised PVC is widely used for soil, waste and vent lines because it resists corrosion, is light to handle, and joints are made quickly with solvent cement. It also gives a smooth bore that resists blockage.

Question 5Plumbing Tools, Materials and Safety Practices

Which PPE is essential when a plumber is cutting and threading GI pipe, to protect the eyes from flying metal chips?

  1. Cotton cap
  2. Leather apron
  3. Ear muffs
  4. Safety goggles Correct answer.

Explanation

Safety goggles shield the eyes from metal chips, oil splash and dust generated during cutting and threading. Other items protect different parts of the body and do not guard the eyes.

Question 6Plumbing Tools, Materials and Safety Practices

Before making a soldered capillary joint on copper tube, the tube end and fitting socket are cleaned and then coated with flux. What is the main function of the flux?

  1. To remove oxide and prevent new oxidation during heating Correct answer.
  2. To act as a permanent waterproof seal
  3. To add extra copper to fill the joint
  4. To raise the melting point of the solder

Explanation

Flux chemically removes oxide films from the copper and shields the cleaned surfaces from air while they are heated, allowing solder to wet and flow into the capillary gap. Residue must be wiped off afterwards because flux is corrosive.

Question 7Plumbing Tools, Materials and Safety Practices

A plumber is to bend a 15 mm soft copper tube by hand without kinking it. What is the standard precaution?

  1. Heat the tube to bright red before bending
  2. Clamp the tube in a bench vice and hammer it to shape
  3. Fill the tube with fine dry sand or use a bending spring before bending Correct answer.
  4. Bend it only after the tube has been filled with water

Explanation

Packing the bore with fine dry sand or inserting a close-fitting bending spring supports the tube wall so it deforms evenly instead of collapsing. The bend is made slowly to the required radius and the sand or spring is then removed.

Question 8Plumbing Tools, Materials and Safety Practices

A plumber needs to join two lengths of 110 mm PVC soil pipe permanently in a trench. Which method is correct?

  1. Apply solvent cement to the cleaned spigot and socket and push together with a quarter turn Correct answer.
  2. Screw the plain ends directly into each other
  3. Wrap the joint with cotton tape only
  4. Seal the joint with plaster of Paris

Explanation

PVC soil pipe is joined with a socket and spigot using solvent cement, which softens the surfaces so they fuse. The parts are cleaned, cement is applied to both surfaces, and the pipe is pushed home with a slight twist to spread the cement evenly.

Question 9Plumbing Tools, Materials and Safety Practices

What is the purpose of a trap in a sanitary drainage system?

  1. To filter solid waste before it reaches the drain
  2. To increase the flow velocity of the discharge
  3. To store water for flushing the fixtures
  4. To retain a water seal that blocks sewer gases from entering the building Correct answer.

Explanation

A trap holds a shallow body of water in its dip, and this water seal prevents foul air and gases from the drainage system from passing back into the building. The seal is renewed each time the fixture is used.

Question 10Plumbing Tools, Materials and Safety Practices

A water closet trap seal is being lost repeatedly because of pressure fluctuations in the stack. Which fitting is installed to protect the trap seal?

  1. Anti-siphon or re-vent pipe Correct answer.
  2. P-trap cleanout plug
  3. Water meter
  4. Floor drain strainer

Explanation

An anti-siphon arrangement, usually a re-vent (back vent) taken from the trap arm, admits air to the fitting so that pressure changes in the stack cannot siphon the water seal away. This keeps the trap seal intact.

Question 11Plumbing Tools, Materials and Safety Practices

Which of the following is the correct working practice when using a ladder to reach a high-level pipe run?

  1. Lean the ladder at 45 degrees and leave it untied
  2. Set the ladder at about 75 degrees to the ground and secure its top Correct answer.
  3. Stand on the top two rungs to gain extra reach
  4. Carry the tool box in one hand while climbing

Explanation

The safe angle for a leaning ladder is roughly 75 degrees (a 4:1 rise-to-base ratio), and the top should be tied or footed so it cannot slip. Both hands should be free for climbing, with tools raised separately.

Question 12Plumbing Tools, Materials and Safety Practices

A plumber is working inside a newly constructed septic tank chamber before commissioning. What is the correct safety action before entry?

  1. Test the atmosphere for oxygen and toxic gases and provide forced ventilation with a standby person outside Correct answer.
  2. Lower a lighted match to check for gas and then enter
  3. Enter quickly while holding the breath to finish the job
  4. Enter alone after spraying air freshener inside

Explanation

Confined spaces such as septic tanks can contain hydrogen sulphide, methane and oxygen-deficient air, so the atmosphere must be tested and ventilated before entry. A standby person outside and a rescue plan are essential because collapse can be immediate.

Question 13Plumbing Tools, Materials and Safety Practices

Which type of valve allows flow in one direction only and prevents backflow in a water supply line?

  1. Gate valve
  2. Globe valve
  3. Check valve Correct answer.
  4. Air release valve

Explanation

A check valve opens with forward flow and closes automatically when flow reverses, so it prevents contamination by backflow. Gate and globe valves are isolating valves controlled by hand and do not stop reverse flow on their own.

Question 14Plumbing Tools, Materials and Safety Practices

A plumber measures a copper tube and finds the outside diameter is 15 mm. Which description correctly matches this tube?

  1. 15 mm inside bore, sized by internal diameter
  2. 15 mm thread size to BSP
  3. 15 mm wall thickness
  4. 15 mm nominal bore copper tube, sized by outside diameter Correct answer.

Explanation

Copper tubes for plumbing are designated by their outside diameter, so a 15 mm copper tube measures 15 mm across the outside with the wall thickness varying by table. This differs from GI pipe, which is normally referred to by nominal bore.

Question 15Plumbing Tools, Materials and Safety Practices

A plumber is fixing a wash basin bracket to a brick wall. Which fixing is most suitable for a firm, load-bearing hold?

  1. Expansion anchor bolt set into a drilled hole Correct answer.
  2. Wooden plug driven into plaster only
  3. Adhesive tape
  4. Nail hammered into the mortar joint

Explanation

An expansion anchor is inserted into a drilled hole and expands against the brick when tightened, giving a secure hold for fixtures carrying load. The hole must be drilled to the correct diameter and depth for the anchor.

Question 16Plumbing Tools, Materials and Safety Practices

Which tool is used to ream the burr from the inside of a cut copper tube before it is soldered?

  1. Basin wrench
  2. Flaring block
  3. Deburring tool or half-round file Correct answer.
  4. Pipe wrench

Explanation

Cutting copper leaves a sharp internal burr that restricts flow and can disturb solder flow, so it is removed with a deburring tool or the smooth side of a half-round file. The outside end is also cleaned before fluxing.

Question 17Plumbing Tools, Materials and Safety Practices

What is the main reason for installing an air gap or a vacuum breaker on a hose bib in a plumbing system?

  1. To increase the water pressure at the outlet
  2. To filter sediment from the supply
  3. To prevent back-siphonage of contaminated water into the potable supply Correct answer.
  4. To reduce the noise of flowing water

Explanation

Backflow protection such as an air gap or vacuum breaker stops a reverse pressure condition from drawing dirty water back into the drinking water supply. This cross-connection control is a basic public health requirement in plumbing.

Question 18Plumbing Tools, Materials and Safety Practices

A plumber is using a hammer and cold chisel to cut a chasing in a brick wall for concealing a pipe. Which precaution is most important?

  1. Work with the face close to the wall to see the line
  2. Wear eye protection and direct the chisel away from the body with a steady, controlled blow Correct answer.
  3. Hold the chisel with the palm of the hand over the head
  4. Wear gloves only and strike as hard as possible

Explanation

Chipping brick throws sharp fragments, so eye protection is essential and the chisel must be held at a safe angle with controlled blows. A mushroomed chisel head should be dressed or discarded to avoid spalling.

Question 19Plumbing Tools, Materials and Safety Practices

Two lengths of 25 mm GI pipe must be joined in a straight run. Which fitting is used?

  1. Socket (coupling) Correct answer.
  2. Tee
  3. Elbow
  4. Reducer

Explanation

A socket, also called a coupling, has internal threads at both ends and joins two pipes of the same nominal size in a straight line. Elbows change direction and tees branch off, so neither suits a straight joint.

Question 20Plumbing Tools, Materials and Safety Practices

A plumber notices that a galvanised steel cold water pipe has developed a leak at a threaded joint after several years. Which is the most likely cause?

  1. The water pressure was too low
  2. The pipe was painted on the outside
  3. The pipe was installed with copper fittings
  4. The galvanised coating was cut away at the thread and the exposed steel corroded Correct answer.

Explanation

Cutting a thread removes the zinc coating and exposes bare steel, which then corrodes preferentially at the joint. This is why threaded GI joints are often protected with a jointing compound or paint after assembly.

Question 21Plumbing Tools, Materials and Safety Practices

A drainage stack serving several floors is being installed. Why is a vent pipe run alongside it to the open air above roof level?

  1. To equalise pressure in the stack so trap seals are not siphoned Correct answer.
  2. To carry the discharge to the sewer
  3. To supply fresh water to the fixtures
  4. To support the stack mechanically

Explanation

The vent admits air to the drainage system, balancing pressure as slugs of waste fall down the stack so that trap seals are not sucked out. It also allows foul air to escape above roof level away from windows.

Question 22Plumbing Tools, Materials and Safety Practices

A plumber pressure-tests a newly installed concealed cold water line at 1.5 times the working pressure. Why is the test pressure held for a specified period before the pipe is concealed?

  1. To speed up the setting of the jointing compound
  2. To stretch the pipe to its final length
  3. To sterilise the pipe with high pressure
  4. To reveal leaks or joints that would otherwise be hidden permanently Correct answer.

Explanation

A pressure test held for the specified duration shows whether any joint or length leaks while it can still be reached. Once the pipe is buried or boxed in, a hidden leak would be costly and damaging to repair.

Question 23Plumbing Tools, Materials and Safety Practices

A plumber must select a pipe material for a hot water distribution line operating at about 70 degrees Celsius. Which choice is most suitable?

  1. CPVC or PPR Correct answer.
  2. Asbestos cement
  3. Polythene (PE)
  4. Standard PVC-U

Explanation

CPVC and PPR are rated for hot water service and retain strength at around 70 degrees Celsius. Standard PVC-U softens at much lower temperatures and polythene is intended for cold water or underground use.

Question 24Plumbing Tools, Materials and Safety Practices

During a site inspection, a plumber finds that the water seal of a floor trap has been lost. Which condition most directly explains this?

  1. The trap is made of PVC
  2. The floor drain has a strainer
  3. The drain has a slight fall
  4. Evaporation or siphonage has emptied the trap Correct answer.

Explanation

A trap seal is lost when the water evaporates during long disuse or is siphoned out by pressure changes in the drainage system. The remedy is to refill the trap and correct any venting defect causing siphonage.

Question 25Sanitary Fittings, Fixtures and Appliances

Which sanitary fitting is installed at the lowest point of a drainage line to allow periodic removal of accumulated debris?

  1. A vent pipe cowl
  2. A rodding eye Correct answer.
  3. A bottle trap
  4. A bib cock

Explanation

A rodding eye is a screwed access fitting placed at the foot or end of a drain so that a drain rod can be inserted to clear a blockage. Traps, taps and vent cowls serve entirely different functions in the system.

Question 26Sanitary Fittings, Fixtures and Appliances

In a water closet, the purpose of the trapway built into the pan is to:

  1. Increase the flushing velocity of the cistern water
  2. Support the weight of the user above the floor
  3. Retain a water seal that blocks foul gases from entering the room Correct answer.
  4. Provide a connection point for the soil pipe joint

Explanation

The integral trap of a WC pan holds a body of water after each flush, and this seal prevents sewer gas from travelling back into the building. Its shape also influences flush performance, but gas sealing is its essential sanitary role.

Question 27Sanitary Fittings, Fixtures and Appliances

A wash basin is to be fitted with a fitting that closes the waste outlet and can be opened by lifting a knob on the tap body. Which waste fitting suits this arrangement?

  1. A float valve
  2. A pop-up waste Correct answer.
  3. A bottle trap
  4. A floor gully

Explanation

A pop-up waste uses a rod or cable linkage from the tap or a knob to raise and lower the waste plug, letting the basin be filled or emptied. It is a fixture-level waste control, distinct from traps and supply valves.

Question 28Sanitary Fittings, Fixtures and Appliances

Which material is most commonly specified for a modern soil and waste pipe because it is light, corrosion resistant and joined by solvent cement?

  1. Cast iron
  2. Galvanised mild steel
  3. uPVC Correct answer.
  4. Asbestos cement

Explanation

Unplasticised polyvinyl chloride (uPVC) soil and waste pipe is lightweight, resists most domestic chemical attack and is assembled with solvent cement joints. Older metallic and cementitious materials are heavier and need different jointing methods.

Question 29Sanitary Fittings, Fixtures and Appliances

The float-operated valve inside a flushing cistern stops the inflow of water when:

  1. The flush handle is pressed down
  2. The overflow pipe discharges to the outside
  3. The outlet valve seat becomes worn
  4. The water level reaches the set height and lifts the float arm Correct answer.

Explanation

As the cistern fills, the rising water lifts the float, and the linkage closes the inlet valve at the pre-set level. This level control keeps the cistern from overflowing during normal operation.

Question 30Sanitary Fittings, Fixtures and Appliances

In a sanitary system, the main purpose of a water seal trap below a fixture is to:

  1. Prevent foul air and gases from the drain entering the building Correct answer.
  2. Reduce the noise of water discharging through the stack
  3. Increase the flow rate of waste water from the fixture
  4. Filter solid matter before it enters the soil pipe

Explanation

A trap holds a measured depth of water, usually between 25 mm and 75 mm, that forms a barrier against sewer gases. The seal is the sanitary safeguard; flow rate, screening and noise control are separate design concerns.

Question 31Sanitary Fittings, Fixtures and Appliances

Which fixture is designed to receive and discharge soil from a water closet directly into the drainage system?

  1. A soil appliance connection to the WC pan outlet Correct answer.
  2. A floor gully in a bathroom
  3. A bib tap over a washing area
  4. A kitchen sink with a basket strainer

Explanation

The WC pan outlet is the soil appliance connection that carries faecal matter into the soil pipe. Sinks, gullies and taps handle waste water or supply water and are classified differently.

Question 32Sanitary Fittings, Fixtures and Appliances

A 100 mm diameter soil pipe serving a WC is being laid. What is the recommended minimum gradient for satisfactory self-cleansing flow?

  1. About 1 in 1000
  2. About 1 in 60 Correct answer.
  3. About 1 in 5
  4. About 1 in 400

Explanation

For a 100 mm soil pipe a fall of roughly 1 in 60 (about 18 mm per metre) is commonly recommended so that solids are carried along and the pipe is self-cleansing. Flatter gradients risk deposition, while very steep falls can leave solids behind.

Question 33Sanitary Fittings, Fixtures and Appliances

A trap has a seal depth of 40 mm. During discharge from a nearby fixture the pressure in the drain fluctuates. What is the main risk to this trap?

  1. Corrosion of the trap body
  2. Blockage of the trap by scale
  3. Frost damage to the seal water
  4. Loss of seal by induced siphonage Correct answer.

Explanation

Pressure changes in the drainage stack can suck or blow the water out of a trap, and a shallow seal is lost more easily than a deep one. This is why traps are sized with adequate seal depth and vents are provided to equalise pressure.

Question 34Sanitary Fittings, Fixtures and Appliances

A wash basin trap is being selected for a fixture with a 32 mm waste outlet. Which fitting is most appropriate to provide the water seal and permit rodding?

  1. A 32 mm P-trap with a cleaning eye Correct answer.
  2. A 100 mm bottle gully
  3. A 50 mm rodding eye on the soil stack
  4. A 15 mm float valve

Explanation

A P-trap sized to the 32 mm basin waste gives the required seal and, with a cleaning eye, allows the trap to be cleared without dismantling. The other fittings are of the wrong size or serve supply or drain-access duties.

Question 35Sanitary Fittings, Fixtures and Appliances

Why is a vent pipe connected to a drainage stack above the highest fixture branch?

  1. To supply fresh water to the cisterns
  2. To increase the discharge velocity in the stack
  3. To collect rainwater from the roof
  4. To equalise pressure in the stack and protect trap seals Correct answer.

Explanation

The vent admits air to the stack so that pressure variations caused by discharge are relieved, which prevents traps from being siphoned. It is part of the drainage system, not a water supply or rainwater route.

Question 36Sanitary Fittings, Fixtures and Appliances

A dual-flush cistern offers 6 litre and 3 litre flush volumes. What is the practical reason for the smaller flush?

  1. To increase the water seal depth in the pan
  2. To raise the flush velocity to the soil pipe
  3. To clear liquid waste using less water Correct answer.
  4. To shorten the refill time of the cistern

Explanation

Dual-flush cisterns give the user a reduced volume for liquid waste, saving water while the full flush remains available for solids. Seal depth, refill time and pipe velocity are not the purpose of the second button.

Question 37Sanitary Fittings, Fixtures and Appliances

A floor gully in a bathroom is fitted with a removable grating and a trap below. What is the main function of the grating?

  1. To retain hair and debris while allowing water to pass Correct answer.
  2. To connect the gully to the vent pipe
  3. To regulate the flow of water into the gully
  4. To provide the water seal against foul gas

Explanation

The grating acts as a coarse strainer so that hair and debris do not enter and choke the trap or outlet. The seal is formed by water in the trap body, and venting is handled by separate pipework.

Question 38Sanitary Fittings, Fixtures and Appliances

A bib tap installed outdoors in a cold region is fitted with a loose key and a drain cock. What is the drain cock used for?

  1. Measuring the flow through the tap
  2. Filtering grit from the supply
  3. Increasing the water pressure at the tap
  4. Emptying the pipe section to prevent frost damage Correct answer.

Explanation

A drain cock allows the isolated length of pipe to be emptied so that standing water cannot freeze and burst the pipe. It is a maintenance fitting, not a pressure, filtration or metering device.

Question 39Sanitary Fittings, Fixtures and Appliances

Which tap type delivers a measured, pre-set volume of water and then closes automatically, making it suitable for public washrooms?

  1. A float-operated cistern valve
  2. A bib tap with a hose union
  3. A pillar tap with a compression washer
  4. A push-button self-closing tap Correct answer.

Explanation

A self-closing tap opens when pressed and shuts off after a timed or metered discharge, which limits water use in public facilities. Pillar and bib taps stay open until turned off, and a float valve is a cistern control.

Question 40Sanitary Fittings, Fixtures and Appliances

A urinal is fitted with an automatic flushing cistern. Which fitting controls the interval between flushes?

  1. A siphon or solenoid flush device with a timing mechanism Correct answer.
  2. A rodding eye on the branch drain
  3. A bib tap on the supply main
  4. A bottle trap beneath the urinal

Explanation

Automatic urinal flushing relies on a siphon or solenoid device that is actuated at set intervals, often by a timer or sensor. Traps, rodding eyes and bib taps have no role in timing the flush.

Question 41Sanitary Fittings, Fixtures and Appliances

A fixture trap is installed with its seal depth reduced to 15 mm to save space. What is the likely consequence?

  1. The trap requires no venting at all
  2. The trap becomes more resistant to siphonage
  3. The trap is easily lost by evaporation or pressure fluctuation Correct answer.
  4. The fixture drains more slowly but safely

Explanation

A seal of only 15 mm is well below the usual minimum and is lost quickly by evaporation or by pressure surges in the drain. Shallow seals give less protection, not more, and still need venting.

Question 42Sanitary Fittings, Fixtures and Appliances

A wash basin drains slowly and gurgles when the tap above is run. Which fault best explains this?

  1. A float valve set too high in the cistern
  2. A missing vent cowl on the stack
  3. A drain cock left open outdoors
  4. A partially blocked trap or branch waste restricting flow Correct answer.

Explanation

Slow drainage with gurgling points to a restriction in the trap or branch waste, which also disturbs the seal and lets air gurgle back. The other options affect cistern level, vent termination or outdoor pipe emptying, not basin discharge.

Question 43Sanitary Fittings, Fixtures and Appliances

A 100 mm soil pipe discharges into a 100 mm drain laid at the same diameter. Which arrangement is preferred at the junction to reduce blockage risk?

  1. A reducer to 50 mm immediately after the junction
  2. A swept bend or oblique junction in the direction of flow Correct answer.
  3. A sharp 90-degree tee with a square branch
  4. A rodding eye fitted on the branch itself

Explanation

Swept bends and oblique junctions guide the flow smoothly and reduce the chance of solids catching at the joint. Sharp square junctions create eddies and are avoided on soil drainage.

Question 44Sanitary Fittings, Fixtures and Appliances

A trap with a 75 mm seal is fitted to a fixture that is used only occasionally in a hot, dry room. Which measure best protects the seal between uses?

  1. Reduce the trap seal to 20 mm
  2. Replace the trap with a rodding eye
  3. Fit an anti-evaporation seal or arrange periodic priming Correct answer.
  4. Increase the branch gradient to 1 in 10

Explanation

Where a fixture is rarely used, the seal can evaporate and allow gas through; an anti-evaporation device or a priming arrangement keeps the barrier intact. Steepening the branch, removing the trap or reducing the seal would worsen the problem.

Question 45Sanitary Fittings, Fixtures and Appliances

A multi-storey building has a soil stack with branches from WCs on each floor. Which combination best protects the trap seals against pressure surges?

  1. A single large trap shared by all the WCs
  2. A stack with all branches connected by square tees
  3. Sealed stack with no vent and shallow traps
  4. A vented stack with branch ventilating pipes and correctly sized traps Correct answer.

Explanation

Venting the stack and branches relieves the pressure changes caused by falling discharge, and correctly sized traps resist loss of seal. Square tees, an unvented stack or a shared trap would all increase the risk of seal loss and cross-contamination.

Question 46Sanitary Fittings, Fixtures and Appliances

A bottle trap below a basin is being replaced. Which detail is most important to check before accepting the new trap?

  1. That it is made of the same colour as the basin
  2. That its seal depth meets the minimum and it can be cleaned Correct answer.
  3. That it is larger than the branch waste pipe
  4. That it has no removable base

Explanation

The replacement trap must hold an adequate water seal and allow cleaning, since these are the sanitary functions of the fitting. Colour, oversizing and a sealed base are not acceptance criteria and can even hinder maintenance.

Question 47Sanitary Fittings, Fixtures and Appliances

A cistern continues to trickle into the pan long after the flush has completed. Which component is the most likely cause?

  1. The water supply pressure being too high
  2. The overflow pipe connected to the drain
  3. The float arm set too low
  4. The flush outlet valve not seating correctly Correct answer.

Explanation

Continuous trickling after the flush indicates that the outlet valve is not sealing on its seat, so water passes into the pan. A low float setting, the overflow route and supply pressure affect filling or overflow, not the flush outlet seal.

Question 48Sanitary Fittings, Fixtures and Appliances

A new bathroom has a basin, a WC and a floor gully connected to one branch drain. Which statement about the trap arrangement is correct?

  1. The gully needs no trap because it is at floor level
  2. Each fixture must have its own trap before connecting to the branch Correct answer.
  3. One trap at the branch end can serve all three fixtures
  4. The WC pan trap may be omitted if the branch is vented

Explanation

Every fixture discharging to the drainage system needs its own trap so that each seal protects that fixture and cross-contamination between fixtures is avoided. A single shared trap, an untrapped gully or an untrapped WC would all allow foul air into the room.

Question 49Water Supply Systems and Pipe Layout

In a municipal water supply system, which component is used to store treated water and maintain steady pressure during peak demand?

  1. Service reservoir Correct answer.
  2. Air release valve
  3. Water meter
  4. Foot valve

Explanation

A service reservoir stores treated water and balances supply against fluctuating demand, which keeps pressure steadier in the distribution network. Foot valves, meters and air valves perform hydraulic or metering functions but do not store water.

Question 50Water Supply Systems and Pipe Layout

Which pipe material is most commonly specified for buried potable water mains because of its corrosion resistance, flexibility and long service life?

  1. Galvanised iron
  2. Cast iron
  3. Polyethylene (PE) Correct answer.
  4. Asbestos cement

Explanation

PE pipe resists corrosion, tolerates ground movement and is joined by heat fusion, so it is widely used for buried potable water mains. Galvanised iron corrodes, cast iron is rigid and heavy, and asbestos cement is now avoided for health reasons.