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WBCHSE HS Vocational Plumbing study materials
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WBCHSE HS Vocational Plumbing practice questions

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Question 1Trade Fundamentals and Safety

A plumber must cut a 25 mm diameter GI (galvanised iron) water supply pipe to length on site. Which hand tool is the standard choice for making this cut square and burr-free before threading?

  1. Hacksaw with a fine-tooth blade Correct answer.
  2. Tenon saw
  3. Wood chisel
  4. Bolt cutter

Explanation

A hacksaw fitted with a fine-tooth (about 24 TPI) blade is the standard site tool for cutting GI pipe, because it produces a reasonably square cut that can then be filed and reamed before threading. The blade should be tensioned firmly and the cut kept perpendicular to the pipe axis.

Question 2Trade Fundamentals and Safety

While threading a 20 mm mild steel pipe with a hand die, the plumber notices the thread is tearing and the die is very hard to turn. Which action is the correct first response?

  1. Heat the pipe end red hot and continue dry
  2. Apply cutting oil generously and back the die off a quarter turn periodically Correct answer.
  3. Increase the die setting to cut a deeper thread in one pass
  4. Force the die through with a longer handle for extra leverage

Explanation

Torn threads on mild steel usually mean the die is running dry or chips are not clearing. Flooding with cutting oil and backing off periodically breaks the chip, cools the die and produces a clean thread; forcing the tool damages both die and pipe.

Question 3Trade Fundamentals and Safety

In a plumbing workshop, which PPE item is specifically required when cutting and threading galvanised pipe with a power pipe machine?

  1. Safety goggles or a face shield Correct answer.
  2. Rubber insulating gloves rated for live electrical work
  3. A dust respirator with P3 filter
  4. A full-body chemical splash suit

Explanation

Power cutting and threading throws metal chips and cutting-oil spray towards the operator's face, so eye and face protection is the essential requirement. Insulating gloves, chemical suits and dust respirators address hazards that are not the main risk in this operation.

Question 4Trade Fundamentals and Safety

A plumber is preparing to solder a copper tube joint in a domestic kitchen. Which preparation step is essential for a sound capillary joint?

  1. Paint the tube end with zinc-rich primer
  2. Leave the tube end as supplied and rely on the solder alone
  3. Coat the tube end with thread-sealing tape
  4. Clean the tube end and fitting socket to bright metal and apply flux Correct answer.

Explanation

Capillary soldering depends on molten solder being drawn into a narrow, oxide-free gap by capillary action. Abrading both surfaces to bright metal and applying a suitable flux removes oxide and lets the solder flow evenly around the joint.

Question 5Trade Fundamentals and Safety

A plumber must isolate a section of a cold water distribution pipe to replace a damaged fitting. Which valve type allows gradual flow regulation and is normally fitted in-line on the pipe?

  1. Check valve
  2. Pressure relief valve
  3. Float valve
  4. Gate valve Correct answer.

Explanation

A gate valve is an in-line isolating valve whose gate is raised or lowered by a handwheel, allowing gradual opening and closing and full-bore flow when open. It is the standard choice for isolating a pipe section for maintenance.

Question 6Trade Fundamentals and Safety

A plumber is installing a water closet in a ground-floor toilet. Which component is placed between the WC pan and the soil pipe to prevent foul gases from entering the room?

  1. A stopcock
  2. A water seal trap Correct answer.
  3. A pressure-reducing valve
  4. An air admittance valve on the pan outlet

Explanation

The water seal trap retains a plug of water that blocks soil pipe gases from reaching the room. The WC pan has an integral trap, but where a separate trap is used it must be fitted between the pan and the soil pipe.

Question 7Trade Fundamentals and Safety

During a pressure test of a newly installed cold water pipe run, the pressure gauge reading falls steadily over ten minutes with all outlets closed. Which is the most likely cause?

  1. The gauge has been fitted upside down
  2. An undetected leak or a loose joint in the run Correct answer.
  3. The water temperature is too low
  4. The pump is too powerful for the pipe

Explanation

In a closed, fully vented system the pressure should hold steady once the pump is isolated. A continuous fall indicates water escaping, typically through an imperfect joint, a damaged pipe or a faulty valve, so the run must be inspected before being concealed.

Question 8Trade Fundamentals and Safety

A plumber is working in a trench for an underground drainage connection. Which precaution is essential before entering the excavation?

  1. Filling the trench with water to settle the soil
  2. Entering alone to save time before others arrive
  3. Shoring or battering the sides and checking for buried services Correct answer.
  4. Leaving the spoil heap at the trench edge for easy access

Explanation

Trench collapse is a leading cause of fatal accidents in drainage work, so the sides must be shored, stepped or battered to a safe angle, and buried services located before entry. Spoil should be kept back from the edge and a second person kept at the surface.

Question 9Trade Fundamentals and Safety

Which property of a plumbing material makes it suitable for hot water distribution pipes in a domestic installation?

  1. Low thermal expansion and resistance to temperature up to about 80 °C Correct answer.
  2. High electrical conductivity
  3. High porosity to allow water absorption
  4. Ability to melt at 60 °C

Explanation

Hot water pipes must withstand continuous service temperatures without softening, deforming or expanding excessively. Copper and cross-linked polyethylene both meet this requirement, whereas materials that soften at low temperature or absorb water are unsuitable.

Question 10Trade Fundamentals and Safety

A plumber is fitting a washbasin in a public toilet block. Which fitting is required to prevent contamination of the drinking water supply by backflow from the basin?

  1. A non-return valve on the drain
  2. An air gap or a suitable backflow prevention device Correct answer.
  3. A gate valve on the supply branch
  4. A water meter on the branch

Explanation

Backflow prevention relies on an air gap or a mechanical backflow prevention device between the potable supply and the fixture. This stops contaminated water from being drawn back into the mains if supply pressure drops.

Question 11Trade Fundamentals and Safety

In a plumbing workshop, a gas cylinder used for brazing is stored. Which practice complies with basic safety requirements?

  1. Store upright, secured against falling, away from heat and with the valve cap fitted Correct answer.
  2. Lay the cylinder on its side under a workbench
  3. Keep it in a locked room without ventilation
  4. Store it next to the oxy-acetylene set with regulators attached

Explanation

Compressed gas cylinders must be stored upright and restrained so they cannot fall, protected from heat and impact, and fitted with valve protection caps when not in use. Good ventilation and separation from other gas sets reduce the risk of fire and asphyxiation.

Question 12Trade Fundamentals and Safety

A plumber is measuring a pipe run to be installed between two walls. Which practice gives the most accurate cut length?

  1. Measure by eye and cut slightly long
  2. Cut the pipe to the nearest metre and adjust with extra fittings
  3. Measure the old pipe after removing it and copy it exactly
  4. Measure between the two fitting centres and add the allowances for the socket depths Correct answer.

Explanation

Accurate pipe lengths are worked out from the distance between fitting centres plus the correct allowance for the depth of each socket or thread engagement. This avoids short pipes that will not reach and long pipes that stress the fittings.

Question 13Trade Fundamentals and Safety

A plumber is joining a 110 mm PVC soil pipe. Which method is the standard for a permanent, watertight joint?

  1. Push-fit with a rubber gasket only, without any adhesive
  2. Solvent cement applied to a cleaned and primed spigot and socket Correct answer.
  3. Compression ring on the plain pipe end
  4. Screwed thread with PTFE tape

Explanation

PVC soil pipes are normally joined by solvent welding: the spigot and socket are cleaned, primed and coated with solvent cement, which softens the surfaces and fuses them into a continuous joint. This produces a strong, watertight connection.

Question 14Trade Fundamentals and Safety

Which document in a plumbing installation provides the correct pipe diameter, gradient and material for each section of the work?

  1. The tool inventory card
  2. The working drawing and specification Correct answer.
  3. The safety data sheet for the solvent cement
  4. The store issue register

Explanation

Working drawings and the specification define pipe sizes, gradients, materials and fitting positions for the installation. Other documents record safety information, tools or stores but do not give installation dimensions.

Question 15Trade Fundamentals and Safety

A plumber must drill a hole through a reinforced concrete wall for a pipe sleeve. Which precaution is most important before starting?

  1. Remove the dust extraction to improve visibility
  2. Confirm there are no concealed electrical cables or water pipes in the drilling zone Correct answer.
  3. Drill without a template to save setting-out time
  4. Increase the drill speed to finish quickly

Explanation

Before any penetration of a wall or floor, the plumber must check drawings and use a cable and pipe detector to confirm the drilling zone is clear of services. Striking a live cable or water pipe can cause fatal injury or flooding.

Question 16Trade Fundamentals and Safety

A plumber is working with a two-part epoxy adhesive for a repair. Which control measure is the most important when handling the resin and hardener?

  1. Wear a high-visibility vest only
  2. Wear nitrile gloves and work in a ventilated area Correct answer.
  3. Wear cotton gloves and work in a sealed room
  4. Use bare hands but wash afterwards

Explanation

Epoxy resins and hardeners are skin sensitisers and can cause dermatitis and allergic reactions, so nitrile gloves and good ventilation are the key controls. A high-visibility vest or bare hands offer no protection against chemical contact.

Question 17Trade Fundamentals and Safety

A plumber notices that a length of lead pipe is present in an old domestic cold water supply. Which action is the correct one?

  1. Increase the water pressure to flush the lead away
  2. Replace the lead section with a suitable approved material and inform the customer Correct answer.
  3. Paint the outside of the lead pipe and continue
  4. Leave it in place because lead is durable

Explanation

Lead can dissolve into drinking water and cause serious health effects, particularly in children. The correct response is to remove and replace the lead section with an approved material such as copper or MDPE and to explain the reason to the customer.

Question 18Trade Fundamentals and Safety

Which unit is used to express the pressure of water in a plumbing installation?

  1. Kilowatt (kW)
  2. Litre per second (L/s)
  3. Kilogram per cubic metre (kg/m³)
  4. Kilopascal (kPa) Correct answer.

Explanation

Pressure is force per unit area and in plumbing is commonly expressed in kilopascals or bar. Kilowatts measure power, litres per second measure flow rate and kilograms per cubic metre measure density.

Question 19Trade Fundamentals and Safety

A plumber is testing a newly installed drainage stack. Which test is appropriate to confirm the pipework is sound before it is concealed?

  1. A smoke test of the water supply pipe
  2. An air or water test of the stack, with all joints checked for leakage Correct answer.
  3. A visual inspection of the outside of the pipe only
  4. A flow test with a single tap open

Explanation

Drainage stacks are tested by filling with water or by air pressure, then inspecting every joint for leakage or pressure loss. This confirms the joints are sound before the pipe is boxed in or buried.

Question 20Trade Fundamentals and Safety

A plumber is fitting a cold water storage cistern in a roof space. Which requirement must be met to protect the stored water?

  1. Leave the cistern open for ventilation
  2. Fit a close-fitting lid and keep the cistern clear of contamination sources Correct answer.
  3. Connect the overflow to a soil pipe without a trap
  4. Place the cistern directly on the roof insulation without support

Explanation

A cold water storage cistern must be covered with a close-fitting lid to stop dust, insects and vermin entering the water. It also needs a supported base and a correctly discharged overflow, not an untrapped soil connection.

Question 21Plumbing Materials, Tools and Equipment

Which material is most commonly used for manufacturing modern cold-water supply pipes because it resists corrosion and has a long service life?

  1. Cast iron
  2. Asbestos cement
  3. Galvanised iron
  4. Unplasticised polyvinyl chloride (uPVC) Correct answer.

Explanation

uPVC is the standard material for modern cold-water supply lines because it does not corrode, is lightweight, and has a smooth bore that resists scale build-up. Galvanised iron and cast iron both corrode over time, and asbestos cement is no longer acceptable for potable supply.

Question 22Plumbing Materials, Tools and Equipment

A plumber needs to cut a 100 mm diameter cast iron soil pipe on site. Which tool is most appropriate for this task?

  1. Tin snips
  2. Chain pipe cutter or disc cutter Correct answer.
  3. Hacksaw with a fine-tooth blade
  4. Wood saw

Explanation

Cast iron soil pipe is thick and hard, so a chain pipe cutter or an abrasive disc cutter is used to make a clean, square cut. A hacksaw is too slow and inaccurate for this diameter, and wood saws or tin snips cannot cut cast iron.

Question 23Plumbing Materials, Tools and Equipment

What is the primary purpose of a pipe wrench (Stillson wrench) in plumbing work?

  1. Measuring pipe diameter
  2. Bending copper tubing to shape
  3. Gripping and turning threaded pipes and fittings Correct answer.
  4. Flaring the ends of soft copper tube

Explanation

A pipe wrench has serrated, self-tightening jaws that grip the round surface of pipes and fittings, allowing them to be turned during assembly or dismantling. It is not a measuring, bending, or flaring tool.

Question 24Plumbing Materials, Tools and Equipment

Which fitting is used to join two pipes of the same diameter in a straight line?

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

Explanation

A socket, also called a coupling, is a short cylindrical fitting that joins two pipes of equal diameter end to end in a straight run. Elbows change direction, tees create a branch, and reducers connect different diameters.

Question 25Plumbing Materials, Tools and Equipment

In a plumbing installation, what is the primary function of a gate valve?

  1. To fully open or fully close the flow of water Correct answer.
  2. To prevent backflow automatically
  3. To regulate flow rate precisely
  4. To release trapped air from the line

Explanation

A gate valve uses a sliding gate that is designed to be either fully open or fully shut, giving minimal resistance when open. It is not intended for throttling or precise flow control, which is the role of globe or needle valves.

Question 26Plumbing Materials, Tools and Equipment

Which type of pipe is typically joined using the solvent cement (solution welding) method?

  1. uPVC pipe Correct answer.
  2. Copper tube
  3. Galvanised steel pipe
  4. Cast iron soil pipe

Explanation

uPVC and CPVC pipes are joined by applying solvent cement, which softens the surfaces so they fuse together as the joint sets. Steel is threaded or welded, cast iron uses caulked or rubber couplings, and copper is soldered or press-fitted.

Question 27Plumbing Materials, Tools and Equipment

What is the purpose of a spirit level when installing a horizontal drain pipe?

  1. To measure the pipe diameter
  2. To cut the pipe square
  3. To check that the pipe is level or has the correct fall Correct answer.
  4. To tighten compression fittings

Explanation

A spirit level shows whether a surface is horizontal or, with a slight reading, whether a pipe has the required gradient for drainage. Correct fall ensures water and waste flow toward the discharge point under gravity.

Question 28Plumbing Materials, Tools and Equipment

Which of the following is a common application of a compression fitting in plumbing?

  1. Sealing a threaded steel joint
  2. Connecting copper tube without soldering Correct answer.
  3. Bending a pipe to a curve
  4. Joining cast iron soil pipe

Explanation

A compression fitting uses an olive (ferrule) compressed by a nut to seal against the pipe, allowing copper or plastic tube to be joined without heat or solder. It is not used for cast iron soil pipe or for bending.

Question 29Plumbing Materials, Tools and Equipment

A plumber is installing a hot-water line and wants a pipe that resists heat well and can be joined by soldering. Which material is the most suitable?

  1. Copper tube Correct answer.
  2. High-density polyethylene (HDPE)
  3. Galvanised iron
  4. uPVC

Explanation

Copper tube withstands high temperatures, resists corrosion, and is readily joined by soldering or brazing, making it a standard choice for hot-water lines. uPVC and HDPE soften at high temperatures, and galvanised iron is prone to internal corrosion.

Question 30Plumbing Materials, Tools and Equipment

When threading a galvanised steel pipe by hand, which tool is used to cut the external thread?

  1. Flaring tool
  2. Pipe die and stock Correct answer.
  3. Tube bender
  4. Pipe reamer

Explanation

A pipe die held in a stock cuts the external thread on the end of a steel pipe so it can accept a threaded fitting. A reamer removes burrs, while flaring and bending tools serve entirely different purposes.

Question 31Plumbing Materials, Tools and Equipment

What is the purpose of applying PTFE thread tape to a threaded steel pipe joint?

  1. To increase the pipe diameter
  2. To strengthen the pipe wall
  3. To lubricate and seal the threads to prevent leakage Correct answer.
  4. To prevent the pipe from corroding internally

Explanation

PTFE tape fills the small gaps between mating threads and acts as a lubricant so the joint tightens smoothly, preventing water leaks. It does not change pipe dimensions, add strength, or provide internal corrosion protection.

Question 32Plumbing Materials, Tools and Equipment

A plumber must join two lengths of 15 mm copper tube in a location where a blowtorch cannot be used. Which jointing method is the most practical alternative?

  1. Lead caulking
  2. Compression fittings Correct answer.
  3. Threading the copper tube
  4. Solvent cement welding

Explanation

Compression fittings seal mechanically using an olive and nut, so they require no heat and are ideal where a blowtorch is unsafe or impractical. Solvent cement does not work on copper, lead caulking is for cast iron, and copper is not normally threaded.

Question 33Plumbing Materials, Tools and Equipment

Which valve is installed to allow flow in one direction only and to prevent backflow in a water supply line?

  1. Air release valve
  2. Gate valve
  3. Float valve
  4. Check valve (non-return valve) Correct answer.

Explanation

A check valve opens under forward flow and closes automatically when flow reverses, preventing contamination or backflow. Gate valves are manual shut-off devices, float valves control tank level, and air release valves vent trapped air.

Question 34Plumbing Materials, Tools and Equipment

A plumber needs to fix a washbasin to a wall and drill holes in a ceramic tile surface. Which tool is most suitable for drilling the tile without cracking it?

  1. Wood bit
  2. Tile bit on rotary mode without hammer Correct answer.
  3. Masonry bit on hammer mode
  4. Hole saw for metal

Explanation

Ceramic tile should be drilled with a tile (carbide or diamond) bit in rotary mode without hammer action, which avoids cracking the brittle glaze. Hammer action, wood bits, and metal hole saws are unsuitable for tile.

Question 35Plumbing Materials, Tools and Equipment

What is the function of a floor drain trap in a sanitary plumbing system?

  1. To filter solid waste from the drain
  2. To retain a water seal that prevents sewer gas from entering the building Correct answer.
  3. To measure the flow of wastewater
  4. To increase water pressure

Explanation

A trap retains a small water seal that blocks sewer gases and odours from entering the building through the drain. It does not boost pressure, filter solids, or measure flow.

Question 36Plumbing Materials, Tools and Equipment

Which of the following best describes the correct method of storing uPVC pipes on site?

  1. Stacked horizontally on supports with ends capped to prevent deformation and dirt entry Correct answer.
  2. Left unsecured on exposed ground
  3. Stored in contact with sharp metal edges
  4. Standing them vertically in direct sunlight for long periods

Explanation

uPVC pipes should be stored horizontally on timber supports, with ends capped to keep out dirt and prevent ovalisation. Long exposure to direct sunlight and contact with sharp edges can cause warping and surface damage.

Question 37Plumbing Materials, Tools and Equipment

A plumber is choosing a pipe for a buried underground drainage line carrying soil waste. Which property is most important in the selection?

  1. Ability to transmit heat efficiently
  2. Light colour for visibility
  3. High surface gloss
  4. Resistance to corrosion and ability to carry solids without blockage Correct answer.

Explanation

Buried drainage pipe must resist corrosion from soil and moisture and have a smooth bore and adequate diameter to carry solids without blockage. Gloss, colour, and heat transmission are not relevant to drainage performance.

Question 38Plumbing Materials, Tools and Equipment

What is the purpose of a pipe reamer after cutting a steel pipe?

  1. To remove internal burrs created during cutting Correct answer.
  2. To bend the pipe end
  3. To enlarge the pipe diameter
  4. To cut an external thread

Explanation

Cutting leaves a rough internal burr that restricts flow and can damage fittings, so a reamer is used to smooth the bore. It does not enlarge the pipe, cut threads, or bend the end.

Question 39Plumbing Materials, Tools and Equipment

Which fitting would a plumber select to connect a 50 mm drain pipe to a 40 mm branch line?

  1. 45-degree elbow
  2. Straight socket
  3. Cap
  4. Reducing tee or reducer Correct answer.

Explanation

A reducing tee or reducer allows two different pipe diameters to be connected while also forming a branch. A straight socket joins equal diameters, an elbow changes direction, and a cap closes off a line.

Question 40Plumbing Materials, Tools and Equipment

A plumber is installing a water supply line and wants a valve that can be used to finely adjust the flow rate to a fixture. Which valve is most suitable?

  1. Check valve
  2. Globe valve Correct answer.
  3. Pressure relief valve
  4. Gate valve

Explanation

A globe valve has a plug that moves against the flow, allowing smooth and precise throttling of flow rate. Gate valves are for on/off service, check valves prevent backflow, and relief valves protect against overpressure.

Question 41Plumbing Materials, Tools and Equipment

Which of the following tools is specifically designed to bend soft copper tube without kinking it?

  1. Hacksaw
  2. Pipe reamer
  3. Pipe wrench
  4. Bending spring or lever-type tube bender Correct answer.

Explanation

A bending spring inserted inside the tube, or an external lever-type bender, supports the wall so the copper bends smoothly without collapsing or kinking. Wrenches, reamers, and hacksaws do not bend pipe.

Question 42Plumbing Materials, Tools and Equipment

A plumber finds that a threaded galvanised steel joint keeps leaking even after tightening. Which is the most likely cause?

  1. The pipe diameter is too large
  2. Thread tape was applied in the wrong direction or insufficiently Correct answer.
  3. The pipe is too cold
  4. The water pressure is too low

Explanation

Leaking threaded joints are usually caused by insufficient or incorrectly applied PTFE tape, which fails to fill the gaps between threads. Pipe diameter, temperature, and low pressure are not typical causes of a leaking threaded joint.

Question 43Plumbing Materials, Tools and Equipment

When comparing uPVC and galvanised iron for a cold-water supply line, which statement best reflects a genuine engineering advantage of uPVC?

  1. uPVC has higher impact strength at low temperature
  2. uPVC can withstand higher working temperatures than galvanised iron
  3. uPVC has greater resistance to internal corrosion and lower friction loss Correct answer.
  4. uPVC is easier to thread on site

Explanation

uPVC resists internal corrosion and has a smooth bore that reduces friction loss, giving better long-term flow than galvanised iron. It is more brittle in cold conditions, has a lower temperature limit, and is joined by solvent cement rather than threading.

Question 44Plumbing Materials, Tools and Equipment

A plumber must select a fitting for a soil stack where a branch enters the main vertical pipe at 45 degrees. Which fitting is most appropriate?

  1. Straight coupling
  2. Reducer
  3. 45-degree junction (Y-branch) Correct answer.
  4. End cap

Explanation

A 45-degree junction, often called a Y-branch, allows a branch to enter the stack at a shallow angle that promotes smooth flow and reduces blockage risk. Straight couplings, reducers, and caps do not create an angled branch.

Question 45Plumbing Materials, Tools and Equipment

Why is a trap with a water seal required below every sanitary fixture in a drainage system?

  1. To store water for reuse in the fixture
  2. To reduce the noise of flowing water
  3. To isolate the fixture from sewer gases while allowing waste to pass Correct answer.
  4. To increase the velocity of wastewater

Explanation

The water seal in a trap blocks sewer gases and odours from entering the building while still allowing wastewater to flow through. It does not increase velocity, store water for reuse, or primarily reduce noise.

Question 46Plumbing Materials, Tools and Equipment

A plumber needs to cut a 110 mm diameter uPVC drainage pipe squarely on site before fitting a socket. Which hand tool is designed for this job?

  1. A cold chisel and hammer
  2. A wheel-type plastic pipe cutter Correct answer.
  3. A pipe wrench
  4. A hacksaw with a fine-tooth blade

Explanation

A wheel-type cutter for plastic pipe scores and snaps the pipe around its circumference, giving a square, burr-free end that lets the socket seal properly. A hacksaw can cut plastic but tends to wander and leave a ragged, out-of-square edge that must be filed true.

Question 47Plumbing Materials, Tools and Equipment

A plumber is laying a 100 mm soil pipe at a gradient and needs to check that it falls steadily toward the drain. Which instrument is used for this check?

  1. A spirit level with a graduated fall attachment Correct answer.
  2. A try square
  3. A chalk line
  4. A plumb bob

Explanation

A spirit level confirms whether a pipe is truly horizontal, and a graduated fall (slope) attachment or adjustable vial lets the plumber set and verify a specific gradient such as 1 in 60. This is the standard site method for checking drainage falls.

Question 48Plumbing Materials, Tools and Equipment

A plumber is installing a fixture where the supply must be shut off and the pipework drained for maintenance, and the valve will be operated only occasionally. Which valve type suits this isolating duty?

  1. A check valve
  2. A pressure-reducing valve
  3. A float valve
  4. A gate valve Correct answer.

Explanation

A gate valve is designed as a full-bore isolating valve: when fully open it offers little resistance to flow and it is intended for infrequent on/off operation rather than throttling. That matches the requirement to shut off and drain a section for maintenance.

Question 49Plumbing Materials, Tools and Equipment

A plumber must support a horizontal run of 15 mm copper tube at intervals along a wall. Which fixing method is appropriate for this purpose?

  1. Supporting the tube on loose bricks
  2. Embedding the tube directly in the plaster
  3. Clipping the tube with purpose-made pipe clips spaced at recommended intervals Correct answer.
  4. Lashing the tube to a nail driven into the wall

Explanation

Copper tube must be supported by clips designed for the pipe diameter, fixed at intervals that prevent sagging and vibration and that allow for thermal movement. Direct embedding or makeshift supports damage the tube and prevent inspection and repair.

Question 50Plumbing Materials, Tools and Equipment

A plumber is selecting a fitting to connect two lengths of 22 mm copper tube in a hot-water line concealed above a ceiling, where access afterwards will be impossible. Which jointing approach gives the most reliable permanent connection?

  1. A rubber sleeve held by two hose clips
  2. A soldered capillary fitting Correct answer.
  3. A compression fitting tightened by hand only
  4. A push-fit fitting with the grab ring omitted

Explanation

A correctly made soldered capillary joint fuses the tube and fitting into a single metallic joint and is accepted for concealed work where future access is impossible. Compression and push-fit joints rely on elastomeric seals that can degrade and are generally avoided in inaccessible locations.