1 in 4 rule
Unit 102
How a leaning ladder is set: the foot goes one metre out for every four metres of height, which gives the correct 75 degree angle.
Every term in the City & Guilds 7202-01 Diploma, explained in plain English — 620 words and abbreviations across all 10 units. The vocabulary comes from the standard rather than from general trade usage, because the words on the exam paper are the standard’s words. Where the trade has a second name for something, the definition says so.
How a leaning ladder is set: the foot goes one metre out for every four metres of height, which gives the correct 75 degree angle.
The gutter fall to learn — about 1.7 mm per metre, and what City & Guilds teach. Divide the run by 600: a 12 m run drops 20 mm, an 18 m run 30 mm.
The site standard for power tools. 110 V through a transformer is far less likely to kill you than 230 V. Recognised by yellow plugs.
Everything that must be in place before the walls and floors are closed up: pipework through joists and studwork, waste pipes, and capped and tested pipe ends.
Everything visible, after plastering and decorating: sanitaryware, taps, radiators, boiler and controls, then filling, testing and commissioning.
The normal maximum working week, averaged over 17 weeks. You may opt out in writing, but you cannot be made to.
An appliance at the top of the energy label scale, using markedly less than a poor one doing exactly the same job.
Acrylonitrile butadiene styrene. One of the three waste pipe plastics, and solvent weldable.
The coldest possible temperature, and the start of the kelvin scale. Water freezes at 273 K.
Advisory, Conciliation and Arbitration Service. Free, independent employment advice, and helps settle disputes between employers and employees without going to court.
The record where the details of every workplace accident are written down, however small.
A pH below 7. Acidic water attacks metals, which is why soft water areas see more corrosion.
Turns nuts and compression fittings of varying sizes. Two are better than one — hold the body while you turn the nut.
Treating somebody worse because of their age. It runs both ways: an older worker passed over for training and a young one paid less for the same job are both examples.
Pressurising finished waste pipework with air and watching a manometer for a set time to prove the joints are sound. It is what turns looking at a joint into demonstrating it holds.
Installs and maintains alarm and security systems. The one true specialism on the electrical list, in the way the drainage specialist is on the plumbing list.
A pH above 7.
Two or more metals mixed together. Brass is copper and zinc; solder and gunmetal are alloys too.
The SI unit of electric current. It sits alongside the metre, the second and the kelvin as a base unit. Level 1 only needs the name; Unit 203 at Level 2 uses it properly, with the volt for pressure and the ohm for resistance.
A heavy duty masonry fixing that expands against the sides of the hole. Used for larger loads on a solid wall.
A power tool with a spinning abrasive disc, for chasing walls and cutting through metals and masonry. Also called a disc cutter, and the paper uses both names. It produces the most dust and the most noise of anything on the power tool list.
Association of Plumbing and Heating Contractors. Support to contractors, and encouraging training, knowledge and professional advice.
The person responsible for first aid arrangements and for calling the emergency services, where there is no trained first aider.
The lower minimum wage rate for apprentices. It applies in the first year of an apprenticeship, and after that only to apprentices under 19 — being left on it past that point is the usual way apprentices are underpaid.
Employment combined with study, usually one day a week for two years at Level 2. The route that lets you earn while completing an NVQ.
Designs the building and produces the drawings everyone works from. Where the answer comes from when a drawing is wrong.
The moulding fitted round a door frame where the frame meets the wall. Carpentry, not joinery you would do — the paper lists the carpenter's work as doors, windows, roof, skirting board and architrave, and the last two are the ones people forget.
A textured ceiling and wall coating, very common in houses, which may contain asbestos if applied before 2000. Drilling one is a classic exposure.
A natural mineral fibre used in building before 2000. Disturbing it releases invisible fibres that cause fatal lung disease. If you find it: stop work, inform your supervisor.
Asbestos mixed with cement, used for guttering, downpipes, flue pipes, garage roofs and old cistern bodies. One of the forms a plumber meets most.
Scarring of the lungs caused by breathing asbestos fibres, which makes breathing progressively harder.
Where everyone gathers after an evacuation, so heads can be counted. Leaving site without going to it can have you recorded as missing.
Metal attacked by the air around it. Needs both oxygen and moisture, and is sped up by pollution and salt.
A wood boring bit with a screw point that pulls itself into the timber, giving a cleaner hole than a flat bit.
Water flowing the wrong way, back towards the main. Preventing it is a main purpose of the Water Regulations, and the reason a bi-flow mixer keeps hot and cold apart until the spout.
A plate screwed to the wall to take a Munsen ring, holding the pipe off the surface.
The everyday name for a float operated valve. Ball cock is a third name for the same thing.
A unit of pressure. Roughly 10 metres of water height gives 1 bar, which is how the pressure in a stored system is worked out.
A length of timber screwed to the side of a joist to carry a board end where a cut has landed between joists.
A cordless drill or driver. Often the safest choice, because there is no lead to trip over or cut through.
A mixer where hot and cold reach one spout but stay in separate channels until they leave it, so the two supplies cannot mix inside the tap.
A tap that comes out of the wall rather than up through the appliance. Used on cleaners' sinks and Belfast sinks.
A boiler fuelled by wood — logs, chips or pellets. Counted as low carbon because it only releases the carbon the tree took in while growing.
Attracted to both sexes.
Where the gas burns. The nozzle size is matched to the pipe size — too small and the joint never reaches temperature, too big and everything around it overheats.
One of the four common hand tool faults. A blunt chisel, saw or blade needs more force, and more force is when a tool slips.
100 degrees Celsius at normal atmospheric pressure, where water becomes steam. Under higher pressure water boils above 100.
A wide bladed chisel for cutting bricks and blocks and for lifting floorboards.
The inside measurement of a pipe. Low carbon steel is sized on the bore, unlike copper and plastic — so 15 mm LCS is noticeably fatter than 15 mm copper.
Gas bottles are stored upright, outside, well ventilated and secure. Upright matters most: on its side, liquid gas can reach the valve and leave as liquid rather than vapour.
How far apart gutter brackets or pipe clips go. Too few and the run sags between them, so water stands where it should be flowing.
An alloy of copper and zinc, used for fittings, valves and taps. It is an alloy rather than a non-ferrous metal, which is a common slip.
A screw that does not rust, used where damp or appearance matters. Softer than steel, so it needs a pilot hole or the head shears off.
Unplanned maintenance: work that happens because something has already failed. Bursts, running overflows, dripping taps and blockages.
Turning a die forward about half a turn then back a quarter, so the curl of metal snaps and clears instead of packing into the die and tearing the thread.
One of the five key trades. Brick laying, stone work and concrete block installation — the structure and the outer skin.
The standard for gravity drainage inside buildings. On guttering it gives 1:350 as a maximum fall rather than a target, and permits a gutter to be laid level — so a level gutter is not a fault, even though 1:600 is the taught figure.
The local authority department that checks building work meets the Building Regulations. Notifiable work has to be told to them and then inspected. Worth knowing precisely: asked which organisation makes sure the electricity supplied within homes is safe, the answer is Building Control, not the IET — the IET writes the wiring regulations, Building Control checks the installation complies.
The legal standards building work has to meet, enforced by the local authority. They cover structure, safety, drainage and — increasingly — energy.
A plumber's hazard above most trades: blowtorch, freshly soldered pipework and hot water. Copper holds heat far longer than it looks like it should.
The rough lip of material left on a pipe end by a saw or cutter. Inside it catches waste and builds a blockage; outside it can cut or roll a push fit seal.
Buys the materials — the right ones, in time, at the right price. Also called a procurement officer.
A scanner used before drilling a wall or floor, to find buried cables and pipes. Cables run vertically and horizontally from sockets and switches.
When a screwdriver tip rides up out of the screw recess under load. Caused by a worn tip or the wrong driver, and it takes your knuckles with it.
The way a liquid is drawn into a very narrow gap, against gravity. It is what pulls molten solder right through a soldered fitting.
A liquid being drawn into a narrow gap between two surfaces, against gravity. It is what makes a solder fitting work: the socket is a close fit over the pipe and molten solder is pulled into the gap rather than poured in. Asked as how solder runs into a joint that is upside down, and this is the answer.
A soldered copper joint. The fitting is a close fit on the pipe, and molten solder is drawn into the tiny gap by capillary action, filling the whole joint — even upwards.
The main greenhouse gas driving climate change, and what is released when a fossil fuel is burnt. Written CO2.
An organisation providing advice and guidance on energy saving and conservation.
One of the five key trades. Hanging doors, installing windows and timber roof installation, plus floors and studwork. The trade a plumber talks to most.
The fixing for plasterboard. Plasterboard is a thin sheet with nothing behind it, so an expanding plug has nothing to expand against; a cavity fixing works the other way round, opening out or toggling behind the board and pulling back against it.
Insulation filling the gap between the two skins of an external wall.
The everyday temperature scale: water freezes at 0 and boils at 100. A rise of 1 degree Celsius is the same size as a rise of 1 kelvin.
Skin damage caused by wet cement and plaster, which is caustic as well as abrasive. It belongs to the bricklayer and the plasterer. Deliberately not called a burn, because on the answer key burns belong to the plumber and the electrician.
The replaceable unit in a ceramic disc tap. There is no washer to change, so the whole cartridge goes — and it is handed, so note whether it is hot or cold.
A tap sealed by two ceramic discs rather than a washer. A quarter turn goes from off to full on. Repaired by replacing the cartridge, not by re-washering.
Clay based materials fired hard — basins, WCs and tiles. Hard and easy to clean, but brittle.
A chalked string snapped against a surface to mark a long straight line.
A slight bevel filed on a cut pipe end so it enters a push fit socket without damaging the seal.
The channel cut into a wall or floor screed for pipe or cable to be buried in. Cutting one is called chasing, and it is what the angle grinder is for. On a solid floor a chase is the only way to get pipework below the surface.
Large tongued and grooved sheets used as a floor deck, often glued. Cut over the joists to lift a section.
Added at the sterilisation stage to kill bacteria. It is the stage that makes water safe to drink.
Combined Heat and Power. Generates electricity and uses the heat that would otherwise be wasted, so far less energy is thrown away.
Fast straight cuts in timber and sheet material. Also used, set exactly to the board thickness, to cut floorboard tongues.
A fire fuelled by solids — wood, paper, cloth, plastics.
A fire fuelled by flammable liquids — petrol, oil, solvents, paint.
A fire fuelled by flammable gases — propane, butane, natural gas.
A fire fuelled by metals — magnesium, aluminium swarf.
A fire involving electrical apparatus. Use CO₂ or dry powder, never water or foam.
A hammer for driving nails, with a claw for pulling them out.
Works for the client, on site, checking the work is being done to the drawings and to the right standard.
The person or organisation the building is being built for. They hold the contract with the main contractor, and the clerk of works works for them.
How far apart pipe clips go. Horizontal runs need more support than vertical, and stiffer pipe needs fewer clips: 15 mm horizontal is 0.3 m in plastic, 1.2 m in copper and 1.8 m in steel.
Black label. Class B and electrical. Works by smothering, so it leaves no residue on equipment.
A steel chisel for cutting metal and chasing masonry. Narrower than a bolster, and prone to a mushroom head.
A painted band identifying the grade of low carbon steel — light, medium or heavy. The bore stays the same across grades; the wall thickness changes.
A boiler that heats water as it flows, so there is no cylinder and no cold water storage cistern. An empty loft and airing cupboard are the giveaway.
Generating electricity on site and using the waste heat for heating rather than throwing it away, so almost all the energy in the fuel gets used. Written CHP. Low carbon rather than zero, because something is still being burned.
Filling, testing and setting a system to work at the end of second fix. The last step before it is handed over.
The government register where limited companies and plcs must register and file their accounts. Anyone can look them up.
The compression fitting used on plastic pressure pipe — a nut and olive, as on copper. It still needs a pipe insert.
A nut and seal tightened onto plastic waste pipe, common on traps and appliance connections. Hand tight plus a little — a spanner splits the plastic nut.
Water vapour becoming liquid again as it cools, forming cloud. Also what forms on an uninsulated cold pipe and gets mistaken for a leak.
Heat moving through a solid, passed from particle to particle. Metals conduct well; plastics do not.
An enclosed space with a risk from the atmosphere inside it — a lack of oxygen, or a build-up of gas. Entry needs training and a permit; at Level 1 you recognise one rather than enter it.
The paperwork that must accompany hazardous waste — more than the ordinary waste transfer note used for other waste.
Unwanted substances getting into the water supply. One of the named reasons maintenance must be speedy, because a fault can let contaminated water back into the supply.
A written statement of your main terms: job, pay, hours, holiday, place of work and notice period. You are entitled to one, and it is worth checking against what you were told.
Heat moving through a liquid or gas that moves: warm fluid rises, cool fluid falls, and a current forms. Most of a radiator's output is convection.
Domestic copper pipe, sized on the outside diameter. 15 mm serves basins, WCs, radiators and branches; 22 mm serves baths and main distribution pipes.
A diamond tipped bit that cuts a large clean circle through masonry — for a flue or an extractor.
Water attacking metal, worst where it is acidic or where two different metals touch. It shows as leaks, discoloured water and radiators full of black sludge.
A tapered screw head that pulls down flush with the surface.
A wood screw with a tapered head that pulls down flush with the surface.
A fitting that joins two straight lengths. On low carbon steel it is sometimes called a socket.
Cutting across a floorboard, over a joist, so the cut end has something to sit back down on. Step four of the seven, and it comes after the tongue and groove joints are cut — free the board along its length first, then cut across it.
Drives Phillips and pozidrive screws. Using the wrong one of the two chews the head.
Construction Skills Certification Scheme card. Proves you have the health and safety knowledge for your role, and most sites will not let you through the gate without one. Note: the Level 1 spec prints the name as Construction Safety Certificate Scheme, so that is what the paper wants.
The fixing for wooden floor boards. Square sided and tapered, so it crushes the timber fibres rather than parting them, and grips hard.
From cut pipe ends, broken tile, slipped chisels and swarf. A freshly cut piece of copper will open your hand up.
Oil used when threading steel. It cools the die, lubricates the cut and gives a clean thread. Threading dry ruins dies.
The hardened wheel in a pipe cutter. Replaced when it stops cutting cleanly, because a blunt wheel needs more force and more force crushes the pipe.
Cuts, nicks or taped repairs in a tool's cable. Insulating tape over a damaged lead is not a repair; it is a fault with tape on it.
Removing the rough burr from a cut pipe end, inside and out. A burr catches waste and can cut the seal in a push fit joint.
Removes the burr from a cut pipe end, inside and out. Kept sharp, because a blunt one drags the burr round rather than cutting it off.
A borehole into deep rock. Very clean, because the water has filtered through a long depth of ground.
A small collar that presses a grab ring open so a push fit joint can be released. It is why push fit pipework can be altered later.
Mass for a given volume. Water gets lighter as it gets hotter, which drives gravity circulation and puts the hottest water at the top of a cylinder.
A float valve in which a rubber diaphragm closes against the seat. The moving parts stay out of the water, so it does not seize, and it is quieter.
The hardened ring with cutting teeth that forms a thread as it is turned onto the pipe.
A cold water system where every cold tap is fed straight from the main, so every outlet has mains pressure and drinking quality water.
The government website, which sets out employment law in plain English. One of the two places named for advice; ACAS is the other.
The last step on the progression route: running the business itself. Plenty of people step off the ladder before this and work for themselves as a sole trader instead, which is why the types of company lesson is not academic.
A physical or mental condition with a long term effect on everyday life. One of the nine protected characteristics, and the one that carries an extra duty to make reasonable adjustments.
Treating someone worse because of who they are rather than what they do. Unlawful on any of the nine protected characteristics named by the Equality Act 2010.
Being let go by an employer. There must be fair and reasonable grounds and a proper procedure.
Talking to the person first and calmly, and raising it with your supervisor or the site manager if that does not work — rather than arguing on site.
The last of the six stages: pumping treated water into the mains and out to properties.
An electrician working in houses — rewires, new circuits, consumer units. The electrical mirror of the domestic plumber, and the first of the four specialist electrical organisations the standard names.
A plumber working in people's homes: bathrooms, boilers, repairs and drainage. The most common specialism in the trade.
Two panes of glass with a gap between them, which greatly reduces heat loss through a window.
Holds a downpipe to the wall, and deliberately slightly off it — so the wall behind can be painted and water running down the outside does not stain the brickwork.
Joins lengths of downpipe together. Also called a pipe socket or coupler.
A valve at the lowest point of a system, used to drain it down for repairs.
A plumbing specialism dealing with above and below ground drainage, blockages and repairs.
Sealing the gaps around doors, windows and floors so warm air is not lost.
Clean workwear, company uniform where there is one, and ID if asked. Somebody is letting a stranger into their house.
Finishing a wall or ceiling with plasterboard rather than wet plaster. One of the plasterer's jobs.
Blue label. The all-rounder: classes A, B, C and electrical.
A WC cistern offering a full and a reduced flush, typically 4 to 6 litres against 9 or more on an older single flush. Useless if nobody knows which button is which.
How far a material can be drawn out or bent without breaking. Copper is ductile, which is why it can be bent cold.
Dull surfaces are good radiators and absorbers of heat; shiny surfaces are poor radiators and good reflectors. Why a solar absorber is matt black and radiator foil is shiny.
Breathing in dust from cutting brick, block, plasterboard or timber. Does its damage slowly, which is why people skip the mask.
Light PPE covering nose and mouth against dust. The mark scheme pairs a dust mask or respirator with respiratory problems due to inhaling dust and fumes. A dust mask is for nuisance dust; a respirator is the heavier item for fumes and finer particles.
Protection laid over a customer's floor and furniture. It goes down before you start, not after the first trip through the hall.
The legal responsibility to store, transfer and dispose of waste properly, documented on a waste transfer note. Waste stays your responsibility until it reaches a licensed site.
Electrical Contractors Association. Support services to contractors, building a sustainable industry and enhancing the profile of the industry.
A fitting that changes direction, usually through 90 degrees. Found in every pipework material on the course.
Current passing through the body. Worst for electricians, but a plumber putting a fixing into a wall meets it too — and is less likely to be expecting it.
Cuts threads quickly and consistently by spinning the pipe. Loose clothing, long hair, gloves and rags stay away from it, and you find the foot switch before you start.
One of the five key trades. Lighting wiring, power supply wiring and maintenance of both. Their first fix happens at the same time as yours, so you compete for the same holes.
One of the four named emergencies. Never touch the casualty until the supply is off, or there are two casualties and nobody helping either.
Corrosion that happens when two different metals sit in the same water: the water acts as an electrolyte, a current flows between them, and the less noble metal is eaten away. A different mechanism from the oxygen and moisture kind, and it is why you do not put copper and steel together without thinking.
The escape route and assembly point for a site, given at induction. Going to the assembly point is what stops people going back in to look for you.
Under HASAWA: take reasonable care of yourself and anyone affected by what you do, cooperate with your employer on safety, and report hazards.
Under HASAWA: create a safe working environment, provide PPE free of charge, provide training, and look after the safety and welfare of employees.
A capillary fitting with no solder in it — solder is fed into the mouth of the joint. Cheaper than solder ring, and needs more skill.
LED lamps in place of filament bulbs. They use a fraction of the electricity and last far longer, so they save on replacement as well as running.
An organisation providing advice and guidance on energy saving and conservation.
An I-joist or metal web joist, now standard in new houses. The strength is in the top and bottom flanges, so it must not be cut like ordinary timber — it has pre-formed service holes instead.
The main legislation covering waste disposal, and the source of the duty of care requiring waste to be stored, transferred and disposed of properly.
A float valve with equal pressure on both sides of the diaphragm, so the float only has to overcome friction. Used on high or fluctuating mains pressure.
Works out what a job will cost so the firm can price it.
Liquid water becoming vapour, driven by the sun. The first stage of the water cycle.
The gap left at each plastic joint so the pipe can grow when it warms. Most fittings carry an insertion depth mark that sets it for you.
Two figures. Water to steam expands about 1600 times; water to ice expands about 10%. Almost every other substance shrinks when it freezes.
A gentle curve deliberately left in a long hot run of plastic pipe, so it has somewhere to go as it expands. Pulled dead straight and clipped tight, it pushes against its own joints.
A sealed vessel with a diaphragm and a gas cushion that takes up the extra volume when water in a system is heated. Water expands about 4% between freezing and boiling (about 2% up to the 60 to 65 °C of a hot water cylinder) and has to go somewhere. Without a vessel, the pressure rises until a relief valve lets water out.
Closes the end of a gutter by fitting over the outside of it. The usual kind, where there is room outside the gutter end.
The valve in the footpath or boundary, belonging to the water supplier, that shuts off the whole property. Turned with a stopcock key.
A loft in August, an unheated new build in January, a whole day outside. Both ends make people careless, which is the second-order problem.
Goggles or safety glasses. Protects against dust and dirt, and against chemical splash. The lightest and most ignored item on the list.
Sterile water kept beside the first aid box for flushing something out of an eye. Solvent splashes, flux, grit and dust are everyday plumbing risks and the treatment for all of them is the same: flush it, for longer than feels necessary, and get it looked at.
The flat board fixed along the ends of the roof rafters. Nearly all guttering hangs from it. Written both fascia and facia; they mean the same board.
A bracket screwed to the fascia board to carry the gutter. Spaced about every metre, and always within about 150 mm of a joint, stop end or outlet.
A metal containing iron — low carbon steel, cast iron. Rusts unless protected, and a magnet sticks to it.
A hand tool for removing rough edges internally or externally. Broader than the deburring tool, and it is what takes the sharp corner off a cut end so it slides past a seal instead of shaving it. Cut square, deburr, chamfer, then joint.
A stage of water treatment where water passes through sand and gravel beds to remove finer particles.
A red square or rectangle showing where fire equipment is — extinguisher, hose reel, alarm point. Not to be confused with the round red prohibition sign.
The three things a fire needs: fuel, heat and oxygen. Remove any one and the fire goes out.
Going back to check an area a good while after hot work has finished. Timber and insulation smoulder for hours before they flame, so the fire usually starts after the operative has left.
A stocked, accessible first aid kit — one of the two minimum requirements at any workplace. Accessible means people can reach it, not locked in a van.
Somebody trained in first aid holding a current certificate. Different from an appointed person, who looks after the arrangements without necessarily being trained.
What the torch flame looks like when it is burning properly — blue and sharp rather than yellow and lazy. A poor flame picture is telling you something: a blocked jet, a low bottle, or a leak.
A device that stops a flame travelling back down the hose towards the bottle.
A flat spade-shaped wood boring bit. Cheap and fast, and the usual choice for drilling joists.
Drives slotted screws. Also what turns most service valves.
What makes plastic pipe quick to run and what makes it sag between clips. It needs roughly four times as many clips as copper for that reason.
The ball on the arm of a float operated valve. One that has taken in water sits low, so the valve never fully closes and the cistern overflows.
A valve that fills a cistern and shuts off at the right level, operated by a float on an arm.
A saw for cutting the tongue along a floorboard. A circular saw set exactly to the board thickness does the same job — set deeper, it cuts what is underneath.
A valve that limits the flow to an outlet so it cannot run faster than it needs to.
The temperature of the water leaving a heat source. Heat pumps work best at lower flow temperatures, which is why they suit bigger radiators or underfloor heating.
The pipe or duct that carries the products of combustion out of a boiler or fire. Old flues are one of the places asbestos hides, and flues are plumbing work — which is why this one is on the list rather than the builder's.
A paste applied before soldering that stops the copper oxidising as it heats and helps the solder flow. Surplus is wiped off, because it corrodes copper.
Dumping waste illegally. A criminal offence — and under the duty of care it remains the producer's offence even when somebody else did the tipping.
Cream label. Use on classes A and B — it blankets a burning liquid. Never on electrical.
The shaped part of a bender that supports the outside of a bend so the pipe keeps its round section. A dented former puts a dent in every bend you make.
Gas, oil and coal. High carbon, because burning them releases carbon that has been locked underground for millions of years.
Waste water containing sewage, as opposed to surface water, which is rainwater. It carries bacteria, so cuts are covered and hands washed before eating.
A long fixing for heavier loads into masonry, used where an ordinary plug and screw would not hold.
0 degrees Celsius, where water becomes ice. Water expands about 10% as it freezes, which is why a frozen pipe splits.
Crumbled easily enough to release fibres into the air. Sweeping or breaking asbestos makes it friable, which is why disturbing it is the whole danger.
Oil burned in a boiler where there is no mains gas, stored in a tank outside. High carbon, for the same reason as natural gas: it is fossil carbon going back into the air.
Opening to the whole inside diameter of the pipe, so nothing is restricted. What a gate valve does, and why it is used on low pressure gravity work.
The current at which a fuse blows. It has to match the tool: one that is too big does not protect the tool or the lead.
A zinc coating on steel to prevent corrosion, by keeping oxygen and moisture off the metal underneath.
A shaped seal squeezed between two flanges or faces to make the joint watertight or gastight. In old pipework and plant the gasket may be asbestos, so an old flanged joint is not one to grind or scrape at.
A valve with a round wheel head used on low pressure gravity pipework. A gate lifts clear of the bore so the flow is not restricted.
The seal around a tap or valve spindle. Water weeping up the spindle rather than from the spout means the gland needs tightening or re-packing.
PPE with two named reasons: hot materials, and sharp implements and tools. Never worn near a rotating tool, where a caught glove takes your hand with it.
Keeping the workplace clear of waste and offcuts. It is the single biggest fire prevention measure, and it is also a named way of reducing material wastage.
The government website, and one of the two employment law information sources the standard wants. It tells you what the law says; ACAS is the other one, and gives advice and conciliation. Older material calls it direct.gov, and it is the same source.
The toothed stainless ring inside a push fit fitting that bites into the pipe and holds it. The O-ring seals; the grab ring grips.
The three wall thicknesses of low carbon steel pipe, identified by a coloured band. Medium is the usual grade for domestic heating.
The slight slope of a gutter towards the outlet. Learn 1:600 — about 1.7 mm per metre — which is what City & Guilds teach. BS EN 12056 gives 1:350 as a maximum and permits a level gutter.
Water moving round a system without a pump, because hot water is lighter and rises while cooler water falls.
Supply driven only by the height of stored water above the outlet. Roughly 10 m of height gives 1 bar, so a loft cistern gives a first floor shower very little.
A gas that traps heat in the atmosphere. Carbon dioxide is the main one driving climate change.
Reusing water from baths and basins for jobs that do not need drinking water.
The strip of upward-pointing tacks around the edge of a room that holds a carpet down. Careful lifting a carpet off them.
The trapped fitting at ground level that a downpipe shoe discharges into, taking surface water away below ground. Leave the shoe off and the water runs down the brickwork into the ground at the base of the wall instead.
Cuts metal — pipe, threaded rod, bar. The blade is fitted with the teeth facing forward, because it cuts on the push stroke.
Water containing dissolved calcium and magnesium. Lathers poorly and leaves limescale when heated.
The permanent electrical cabling buried in the walls and floors of a building. Cables run vertically and horizontally from sockets and switches, so the space above a socket is a bad place for a fixing.
How well a material resists scratching, denting and wear. Different from strength, which is about load.
Health and Safety at Work Act 1974. The umbrella law all other health and safety law sits under.
Anything that could cause harm — a trailing lead, an open hole, a bottle of solvent.
Yellow triangle with a black border and symbol. Warns of the danger — danger of electric shock.
A diamond shaped symbol, orange or white with a red border, on containers of hazardous substances — corrosive, toxic, flammable, harmful. A separate system from the five safety signs.
Waste harmful to people or the environment, needing separate containers and its own paperwork: asbestos, waste electrical equipment and solvents. Clean scrap lead is not hazardous waste, though the qualification’s list includes lead.
Ear defenders or plugs, against noise. Hearing damage is gradual and permanent.
A fireproof mat placed behind a joint before soldering, so the flame cannot reach what is behind it.
Takes low grade heat from the air or the ground and raises it to a useful temperature. Delivers more heat than it uses in electricity, because it moves heat rather than making it.
Heat moving from hotter to colder, by conduction through a solid, convection through a moving fluid, or radiation through space.
A plumbing specialism focused on central heating and boilers rather than on sanitation and drainage.
Both propane and MAPP gas are. A leak sinks and collects at low level — a trench, a basement, a van footwell — rather than drifting away, so the lowest place is the dangerous one.
Natural fibre wound into a thread with jointing compound to seal it. It swells slightly when wet, which is why it has been used for a century.
Attracted to the opposite sex.
The order in which hazards are dealt with: eliminate, substitute, engineering control, administrative control, and PPE last. It is why PPE is called the last line of defence.
Energy sources that release a lot of carbon dioxide: natural gas and LPG, fuel oils, solid fuels such as coal and peat, and electricity from non-renewable sources.
A pillar tap with a taller spout, used on kitchen sinks so a bucket fits underneath. That is the reason, not styling.
PPE that makes you clearly seen around site, especially near plant and vehicles. The hazard is a driver genuinely not knowing you are there.
A saddle with a hinge on one side and a catch on the other, so it closes fully round the pipe. The most secure of the three clips on this unit, and the one for a run that will be seen or disturbed.
A cylindrical saw for cutting larger holes in timber, plastic and thin metal.
Attracted to the same sex. A homosexual man is usually called gay; a homosexual woman gay or lesbian.
Secures a gas hose at both ends. Part of the assembly, and part of the visual inspection before every use.
A vessel storing heated water. Hot is drawn from the top, because hot water is less dense and rises.
Health and Safety Executive. The body that enforces health and safety law. Its inspectors can visit a site, issue notices and prosecute.
High Speed Steel drill bit, for metal. Used without hammer action, often with cutting fluid.
A noise fault. While a tap runs it is caused by a worn tap washer vibrating; while a cistern fills, by a worn float valve washer. When the noise happens tells you which.
Bends steel pipe using hydraulic force. There is no hand bender equivalent — this pipe will not bend by hand.
Electricity generated from falling water. A zero carbon source: it releases nothing in use.
Water in its solid state. It is less dense than liquid water, so it floats and ponds freeze from the surface down.
Institution of Engineering and Technology. Responsible for international standardisation of regulations, and the wiring regulations.
A notice from an HSE inspector requiring a fault to be put right by a stated date.
A cold water system where only the kitchen tap is fed from the main and the rest are fed by gravity from a storage cistern.
An electrician working in factories, shops and offices rather than houses. Larger installations, three phase supplies and different regulations. Written industrial commercial electricians in the standard, and it means the same thing.
A plumber working on pipework in factories and on large plant rather than in houses. One of the five specialist plumbing organisations the standard names. The way to sort the five is who would you call: pipework in a factory is the industrial plumber.
Waste that will not rot, burn or react: bricks, glass, ceramics and tiles, sand and gravel.
Green square or rectangle. Safe condition — fire exit, first aid.
Reads a surface temperature without touching it. Useful for checking a pipe or radiator quickly, and for finding which pipe is the flow.
How far a pipe goes into a fitting. On plastic gutter and push fit it is set by a moulded mark, and stopping there is what leaves the expansion gap.
Material that slows heat transfer. Gives energy efficiency and prevents heat loss, and in plumbing also protects pipes from freezing and stops condensation.
The ridge a pipe cutter pushes into the bore. The wheel displaces copper rather than removing it, and the ridge restricts flow and causes turbulence.
Closes a gutter from inside, used where the run finishes tight against a wall and there is no room outside it — a terraced house, for instance.
The valve where the supply enters the building, usually under the kitchen sink. The one used to isolate the house.
Shutting off the supply to part of a system so it can be worked on. Service valves isolate one appliance without draining the whole house.
Joint Industry Board. Responsible for grades, wages, allowances, benefits, employment advice and industrial agreements.
Cuts curves and shapes, and cuts into the middle of a board. The power tool equivalent of a pad saw.
The document saying what is to be installed and to what standard — materials, makes, models and finishes.
A paste used with hemp to seal a screwed joint. The alternative to PTFE tape, and still usual on larger sizes and heating work.
A timber beam carrying a floor or ceiling. Notching and drilling one is limited by Building Regulation Part A.
The small part inside a tap that carries the washer down onto the seating. It lifts out once the headgear is off.
A small hacksaw for cuts in tight spaces, such as copper tube where a full hacksaw will not swing.
The SI unit of temperature, starting at absolute zero. Water freezes at 273 K. A rise of 1 K is the same size as a rise of 1 °C.
The five trades named by the standard: electrician, plumber, carpenter, bricklayer and plasterer.
Boards around the edge of a working platform that stop tools and materials being kicked off onto people below. Also called toe boards.
The prefix meaning a thousand. A kilowatt is a thousand watts and a kilogram is a thousand grams. Its opposite is milli, a thousandth — learn the two prefixes and you can read units you have never seen.
The SI unit of mass, a thousand grams. A litre of water weighs a kilogram, which is worth remembering the next time you carry a full cylinder.
The safe technique for lifting by hand — one part of manual handling, not a separate subject. Feet apart, bend the knees not the back, load close to the body, lift smoothly with the legs, and never twist while carrying.
Leaning access equipment for getting somewhere and for short duration work — not for working from all day. Set at 75 degrees, one out for every four up.
A floating floor, clipped together and laid from a wall. Usually has to come up in sequence rather than in one piece.
Heat that changes the state of a substance without the temperature moving at all — ice to water, water to steam. The 1600 times expansion when water boils is latent heat doing its work.
A heavier cutter with a hardened wheel, for steel pipe. A copper cutter will not touch it.
A fluid brushed onto gas joints that bubbles where gas escapes. Never test for a gas leak with a flame.
A thread that tightens anticlockwise, used on many gas fittings. It is deliberate: it stops a gas fitting being connected to something not meant to carry gas.
Asbestos removal by a licensed contractor with its own training, equipment and paperwork. What happens after you stop work and tell your supervisor.
Taking waste to a site licensed to receive that type of waste. The licence is specific, which is why hazardous waste cannot go to a general tip.
Baths, boilers, radiators, cylinders and bags of plaster — usually through a doorway of the wrong shape and up a staircase.
The hard deposit left when hard water is heated and dissolved calcium comes out of solution. It coats heat exchangers and immersion heaters and wastes fuel.
A business that is legally separate from its owners, with private shares. 'Limited' means the owners' personal money is protected if the company fails.
Liability means legal responsibility for a debt. Limited liability means the owners of a company lose only what they put in if it fails — their personal money is protected. It is what the word 'limited' refers to, not the size of the firm.
The unit of volume for water, symbol L. Usefully, 1 litre of water weighs 1 kilogram — so a 210 litre cylinder holds over 200 kg.
The council. In construction, responsible for the Building Regulations and checking that building work meets the law.
Buying materials near the job. Shorter journeys mean less fuel, and usually a shorter wait when something is missing.
Insulation laid between and over ceiling joists. Part of the cheapest saving there is — heat you never lose costs nothing to replace.
A roof void with five hazards at once: no proper floor, poor light, sharp roofing nails at head height, insulation hiding everything, and extreme heat in summer.
A hammer head loose on its shaft — one of the four common hand tool faults. It will come off, in the direction you were swinging.
Pipe not properly clipped. When the flow stops suddenly it moves and strikes the structure, which is the cause of banging in a system.
Sources that release some carbon but far less: solar thermal, biomass, heat pumps and combined heat and power.
Heavy rigid steel pipe joined by cutting a thread onto it. Also called mild steel. Sized on the bore, not the outside.
Heat that is present but too cool to be useful, in the air or the ground. A heat pump raises it to a useful temperature.
Liquefied petroleum gas — propane or butane. Stored as a liquid under pressure and used as a vapour. A high carbon fuel, and the gas in a plumber's blowtorch bottle.
A heavy hammer for driving a bolster or cold chisel through brick or block.
One of the three asbestos diseases the answer key wants, alongside asbestosis and mesothelioma. Caused by breathing the fibres, and it cannot be cured or reversed. It can take thirty or forty years to show, which is why nothing warns you at the time.
A magnet sticks to ferrous metal and not to copper, brass or lead. A quick way to tell what an old pipe is, and therefore how it is likely to be jointed.
The black iron oxide sludge that collects in a heating system from the inside of steel radiators. The reason systems are flushed and dosed with inhibitor.
The firm holding the contract with the client, responsible for the whole build. They bring in sub contractors for specialist work.
The general purpose drill, for wood, metal and masonry.
An electrician who keeps an existing installation running rather than installing new work — testing, fault finding and repair. The electrical equivalent of the maintenance engineer on the plumbing list.
A plumbing specialism looking after existing installations rather than fitting new ones — planned inspections and breakdown work.
How well a material can be hammered or pressed into shape. Lead is very malleable, which is why it was used for roof flashings.
The fourth step on the progression route. Running jobs rather than running a team on one job — programme, cost and people.
Round, solid blue with a white symbol. Means you MUST do this — eye protection must be worn.
A gauge that measures pressure by the height of a column of liquid, used to read an air test on drainage pipework. Level 1 stops at knowing the name; Unit 209 at Level 2 is where you use one.
Lifting, carrying, pushing or pulling a load by hand — the whole activity, of which kinetic lifting is the safe technique. It injures more workers than almost anything else, usually the back, and usually cumulatively rather than in one moment.
How a specific appliance must be installed. They take priority over everything else: fitting against them voids the warranty and can breach the regulations.
A bottled gas that burns hotter than propane, so it solders larger sizes faster.
A hardened-tip drill bit for brick, block and concrete, used with hammer action.
Material paid for and thrown away. It costs three times: buying it, disposing of it, and replacing it.
Time off around the birth or adoption of a child, which can run up to 52 weeks.
The temperature at which water is heaviest for its volume — 4 °C. It is why ponds freeze from the surface down rather than solid.
Equipment that carries the load instead of you — sack trolley, pipe trolley, pallet truck, lifting straps. It comes before lifting it yourself, not after.
A cancer of the lining of the lungs, caused almost only by asbestos. Can take 20 years to develop after exposure.
A water supply charged by volume used. The household pays once to buy each litre and again to have it taken away as waste water.
A written description of how a job will be done safely, step by step. Read with the risk assessment, it is somebody else's thinking about this job, free.
The SI unit of length, symbol m. There are 1000 mm in a metre, so mm to m is divide by 1000 and m to mm is multiply.
Mobile Elevated Work Platform. A powered platform that lifts you and gives a guarded working area.
Another name for low carbon steel, along with 'iron' on site. All three mean the same pipe.
One thousandth of a metre, symbol mm. Almost everything in plumbing is marked out in millimetres.
The legal hourly minimum. The rate depends on your age, and there is a separate apprentice rate. Rates change every April.
A countersunk screw with a threaded hole in the head to take a chrome dome cap. Used for mirrors and bath panels.
One of the four power tool faults. A guard is not an inconvenience somebody removed to work faster — it is the part that stops the blade reaching you.
A fine toothed saw for cutting plastic waste pipe, guttering and downpipe. Fine teeth give a clean, square cut; a coarse wood saw tears plastic.
A two-part ring that clamps round a pipe and screws to a backplate. The usual way of carrying steel pipe.
The spread, mushroom-shaped end of a chisel or bolster that has been struck repeatedly. Pieces can fly off it, so it is ground back or the tool removed from use.
A clip with a masonry nail through it. Quick, and used for pipework that will be hidden.
Drives an old nail below the surface of a board so nobody kneels on it. Part of the floorboard lifting kit.
The mains gas piped to most houses, and a high carbon energy source because it is a fossil fuel being burned. Grouped with LPG on the paper, and the pair heads the high carbon list.
A pH of exactly 7 — pure water. Below is acidic, above is alkaline.
The line through the middle of a joist where the timber is neither being compressed nor stretched, and so is doing least work. Holes are drilled on it for that reason.
Power tools, cutting and everybody else's work. Hearing damage is gradual and permanent, and there is no day on which you notice it happening.
A metal containing no iron — copper, lead, aluminium, zinc. Does not rust, and a magnet will not stick to it.
Ordinary waste that will break down or be recycled: timber, paper and cardboard, water based glues and paints, and scrap metal, clean scrap lead included.
A source that cannot be replaced once used. Electricity generated from non-renewable sources counts as high carbon.
A cut into the top edge of a joist. Maximum depth is 0.125 (an eighth) of the joist depth, and only between 0.07 and 0.25 of the span from the support.
How much warning each side has to give before ending the job. It is in your written terms, and leaving without working it is a breach of your contract.
National Vocational Qualification. The trade qualification proving you can do the job. A plumber needs NVQ Level 2; an electrician needs Level 3. Partly assessed at work, so it needs employment.
The rubber ring inside a push fit fitting that makes the seal. The pipe end has to be square, round and clean to seat against it evenly.
The short end left after cutting to length. Most waste on a plumbing job is offcuts, and a 300 mm piece of pipe is a tail, a connection or a test piece rather than rubbish.
A pair of bends that steps the downpipe back to the wall from the overhanging gutter. Also called a swan neck.
The unit of electrical resistance — how hard a circuit makes it for current to flow. Named alongside the volt, the ampere and the watt in the electrical units set.
The soft brass ring in a compression joint that is squeezed onto the pipe to make the seal. Once compressed it is not reused.
Real work on real jobs. One of the three things needed to work qualified, and the reason an NVQ cannot be completed at college alone.
The measurement across the outside of a pipe. Waste pipe, copper and plastic pressure pipe are all sized this way; low carbon steel is sized on the bore instead.
Pipe crushed out of round, usually by a blunt pipe slice. It will not seal in any fitting, which makes it a tool fault rather than a technique fault.
Somebody working above you, and anything they might drop. The reason hard hats and kick boards exist.
Leaning out sideways from a ladder rather than moving it. The test is your belt buckle, which should stay between the stiles.
A metal reacting with oxygen and dulling. Flux stops copper oxidising as it heats, which is why a joint is fluxed before it is soldered.
The material in a gland that seals around a spindle. Re-packed when tightening the gland nut no longer stops water weeping up the spindle.
A narrow bladed saw for cutting a hole in the middle of a board, started from a drilled hole.
5.6 weeks a year for a full-time worker — 28 days for somebody working five days a week, and that figure includes bank holidays.
The part of the Building Regulations covering structure, and the source of the rules on notching and drilling joists.
A business owned by two or more people who share the profits and the responsibility for debts.
How to use an extinguisher: Pull the pin, Aim at the base of the fire, Squeeze the handle, Sweep side to side. Aiming at the flames does nothing.
Portable Appliance Test. The label on a power tool showing it has been tested and when the next test is due.
Time off around the birth or adoption of a child for the partner. Normally one or two weeks.
The unit measuring acidity and alkalinity, on a scale of 0 to 14. Below 7 is acidic, 7 is neutral, above 7 is alkaline.
A cross-shaped screw recess, designed so the driver rides out when the screw is tight.
Panels that turn daylight directly into electricity. Not the same as solar thermal, which makes heat.
A tap that rises vertically through a hole in the appliance. 15 mm tails for basins and bidets, 22 mm tails for baths.
A small hole, narrower than the screw, drilled first. It gives the thread somewhere to start and stops the timber splitting.
The fluid used before solvent cement. It removes grease and the release agent left from manufacture and starts softening the surface. Skipping it is the usual cause of a failed solvent joint.
Cuts copper tube square, tightened a quarter turn at a time. Forcing it round crushes the pipe oval, and an oval pipe will not seal.
A short sleeve pushed inside a plastic pipe end to hold it round and rigid. Every joint in plastic pressure pipe needs one — without it the joint can leak or blow apart.
Lagging around pipework. Saves heat, protects pipes in unheated spaces from freezing, and stops condensation forming on cold pipes.
A cutter that cuts plastic pressure pipe square in one action. Never cut this pipe with a hacksaw.
Clips and brackets holding a run in line. Horizontal runs need roughly twice the support of vertical ones, because gravity pulls them out of line rather than along them.
Clamps pipe while it is cut or threaded. Without it the pipe turns instead of the die, and a length of steel pipe swinging round at waist height is a serious injury.
The part that moves sideways in a Portsmouth pattern valve, pressing a washer against the seat. It slides in a bore full of water, which is why it can stick.
Checking equipment at regular intervals before it fails — float valves, appliance taps, stop, gate and isolation valves. Usually on larger installations.
Scale drawings of the building with the services marked. They tell you where everything goes; the specification tells you what, and the schedule when.
A spring toggle, self drilling plug or similar that spreads the load behind a hollow board. An ordinary wall plug pulls straight out of plasterboard.
One of the five key trades. Plastering and dry lining. The trade you hold up if your first fix is late, because nothing can be closed up until your pipework is in.
Spreading a wet coat of plaster onto a wall and smoothing it. The other half of the plasterer's work is dry lining, which is the dry equivalent.
Flexible pipe for hot and cold supply, in the same 15 mm and 22 mm sizes as copper so the two connect directly. No flame is involved anywhere in working it.
Blanks off an unused socket or branch, and seals a system for testing. You cannot test a system that is open at one end.
Truly vertical. The opposite pair to level, which is horizontal. A plumb line finds it using gravity and a weight on a string.
A weight on a string, used to find true vertical — setting a downpipe straight down a wall. A downpipe slightly out is obvious from the street for thirty years.
One of the five key trades. Hot and cold water supply, central heating, bathroom installation, sanitation and drainage — the widest list of the five.
One of the three waste pipe plastics. It cannot be solvent welded at all — cement will not soften it — so it is push fit only.
An older float valve in which a piston moves sideways to press a washer against the seat. The level is set by bending the arm.
A cross recess with extra fine lines between the arms. Grips better than Phillips and is the common site type. A Phillips driver will chew a pozidrive head.
Personal Protective Equipment. The last line of defence when a hazard cannot be removed. Must be provided by the employer free of charge.
Damage already present before you start. Point it out to the customer first — it protects them and protects you from being blamed.
Reduces the high pressure in a gas bottle to a steady working pressure at the torch.
The usual career path in the trade: apprentice, qualified tradesperson, supervisor, manager, director. Working for yourself as a sole trader is the other normal ending.
A notice from an HSE inspector stopping an activity immediately until it is put right. More serious than an improvement notice.
Round, red border with a red diagonal bar on white. Means you must NOT do this — no smoking, no entry.
The common bottled gas for plumbing, in a red bottle. Heavier than air, so a leak sinks and collects at low level.
Overalls. Protects against oils and grease, and keeps loose clothing out of anything turning.
Thin tape wrapped round a thread to seal it. Wrapped in the direction the fitting turns.
A company whose shares can be bought by the public on the stock market. Used by the largest contractors.
The first stage after the river on the water supply diagram: it lifts the water out of the source and moves it on. One of the seven labels the exam asks for, and the easiest to place because nothing comes before it but the river.
Where sterilisation happens: chlorine kills what filtering cannot remove. Fourth of the seven labels on the supply diagram, and the last treatment stage before storage.
A joint where a rubber seal inside the socket grips the pipe. Quick, needs no cement, and can be taken apart.
A plastic clip the pipe snaps into. Used on both copper and plastic pressure pipe.
Polyvinyl chloride. One of the three waste pipe plastics, and solvent weldable.
Measures and values the work so it can be paid for, and prices variations when the job changes. A real job on a large site, but not one of the six roles the standard names for Level 1 — so it turns up as a wrong answer more often than a right one.
A ceramic disc tap that goes from off to full on in a quarter turn. It closes so fast that it makes water hammer more likely, revealing pipework that was always underclipped.
Colour, nationality, ethnic or national origin. One of the nine protected characteristics.
Heat moving as rays through space, needing nothing to travel through. It is how the sun heats a solar panel.
Collecting rainwater for jobs that do not need drinking water, such as flushing a WC or watering a garden.
Residual Current Device. Cuts the supply within milliseconds if current leaks to earth — for example if you cut through your own lead.
Fitting a new washer — the repair for a dripping tap or stop valve. If it still drips afterwards, the seating is scored and needs re-cutting.
A change an employer must make so a disabled person can do the job — different equipment, a changed task, different hours. Refusing an easy one is discrimination.
A power saw whose blade drives back and forth rather than round, for cutting through pipes, timber, sheet metal and conduit. The demolition and first fix saw: it will get through almost anything you point it at, which is exactly why you check what is behind first.
Separating waste that can be reprocessed rather than putting everything in one skip. A mixed skip costs more and recovers nothing.
A fitting joining one size of pipe to another — 22 mm down to 15 mm, or a 32 mm branch joining a 40 mm run.
When a job stops existing because the work has gone or the firm is reorganising. It is about the job, not the person.
The process a heat pump uses to raise low grade heat to a useful temperature. It is a fridge working the other way round: taking heat from outside and putting it into the house.
The valve fitted to the gas bottle that drops cylinder pressure to the working pressure the torch needs. It goes on with a left hand thread, so it tightens anti-clockwise, and the visual inspection before lighting up is to check the thread for damage.
How heavy a substance is compared with water. Water is 1, so anything below floats and anything above sinks. It is the general version of the density changes that drive gravity circulation in a hot water system.
One of the nine protected characteristics. It includes having no religion.
Energy from a source that replenishes itself — wind, tide, falling water, the sun, and wood that is replanted.
Where water is stored in quantity before treatment. Standing still also lets the heaviest particles settle out on their own.
A mask that protects you from inhaling dust and fumes. Must fit properly to work.
Reporting of Injuries, Diseases and Dangerous Occurrences Regulations. Requires an employer to report serious accidents and certain diseases to the HSE.
The cold water pipe running up through the house from the internal stop valve, feeding appliances on the way and the storage cistern at the top.
How likely a hazard is to cause harm, and how bad that harm would be.
Looking for the hazards, deciding who might be harmed, deciding what to do about it, writing it down and reviewing it.
Surface water taken from a river. Plentiful, but the dirtiest of the five sources — it has run over land and through towns.
A domed screw head that sits on top of the surface.
The steps of a ladder. Checked for missing, loose or damaged rungs, and for grease or mud.
The take-off in the middle of a gutter run where the downpipe leaves.
The corrosion product of ferrous metal. It flakes off and exposes fresh metal underneath, so it keeps going — unlike the protective film copper and lead form.
A simple mechanical lifting aid. Where a machine can carry it, use the machine rather than lifting.
The first step in any lift: how heavy and how bulky, how far and is the route clear, can you see over it, are there stairs. Then decide whether to lift, share or mechanise.
The agreed way a job is done safely, as opposed to the equipment used to do it. Part of what an employer must provide.
Boots with a toecap against dropped objects and a midsole plate against nails through the sole. Both are everyday events on a site.
A hard hat. Two named reasons: falling objects, and bumps. The second is far more common than the first.
A written notice rather than a symbol: site rules, permit boards, and the health and safety law poster an employer must display.
A dated label showing access equipment has been inspected. No tag, or an expired one, means it has not been checked.
A dip in an unsupported run of pipe or gutter. It holds standing water, which silts up and blocks, and in a gutter it also freezes and splits joints.
Taking foul and surface water away from a building — soil pipes, waste pipes, gutters and the drains under the ground. One of the four jobs the standard gives the plumber, alongside hot and cold water supply, central heating and bathroom installation. It is why the qualification covers drainage and not only water in.
The drawing showing the size of rooms and the position of equipment, accessories and appliances. Drawn to a ratio, so a measurement on the paper converts to a real measurement on the wall. This is the one you work from.
A drawing showing how a system works rather than where anything is or what size it is. A heating schematic tells you what feeds what, with the pipe runs straightened out to make it readable. If the question mentions sizes or positions it is the scale drawing; if it mentions how a system operates it is the schematic.
A brass saddle screwed to the surface, used where pipe is on show. The cast version is used for low carbon steel.
A hand bender for 15 mm and 22 mm copper that supports the pipe so it does not flatten or kink.
Recyclable metal from a job: copper tube, brass, low carbon steel, copper cable, conduit and galvanised trunking. Lead is recyclable too; clean scrap lead is not hazardous waste, and it is kept apart because it is priced separately.
The usual joint on low carbon steel: a thread cut onto the pipe screwed into a threaded fitting, sealed with PTFE tape or with jointing compound and hemp.
A drill with a hammer action and a special chuck, for drilling masonry and concrete quickly.
The machined face inside a tap that the washer closes against. A scored seating will drip however new the washer is.
The SI unit of time, symbol s.
A stage of water treatment where the water is held still so suspended solids sink to the bottom.
A valve that has corroded or scaled solid from never being operated. Part of planned maintenance is simply turning valves off and on so they still work when needed.
A screw that cuts its own thread as it goes in, used in sheet metal and plastic.
Heat that changes the temperature of something — you can sense it on a thermometer. The pair to latent heat, which changes the state instead.
A hole formed in an engineered joist by the manufacturer for pipes and cables to pass through. Use these rather than cutting your own.
A small isolating valve at an appliance, so one fitting can be shut off for repair without draining the house. Usually turned with a screwdriver.
Measuring and marking a run accurately before cutting. A named method of reducing material wastage, because most offcuts come from cutting short.
Where sedimentation happens: the water is held still and the heavy solids sink out of it. Second stage of the supply process, and the reason the order is not arbitrary — settle the big stuff out before you try to filter the small stuff.
Which sex a person is attracted to. Heterosexual means the opposite sex, homosexual the same sex, bisexual both. Treating somebody worse for it is unlawful, as is doing so because you have assumed it.
A well into the water table near the surface. More easily contaminated from the ground above it than a deep well.
The last fitting at the bottom of a downpipe, angled to throw water away from the wall into a gully.
The internationally recognised units. In plumbing: metre and millimetre for length, second for time, kelvin for temperature, m² for area and litres for volume of water.
The grease used on water fittings. Safe with drinking water and does not attack rubber. Never use oil or ordinary grease.
What a push fit pipe end is lubricated with. Never oil or grease, which attack the rubber seal and destroy it within a year or two.
Water in a full bore of pipe dragging the trap water out behind it by suction, leaving the trap empty. The reason a bath run in 32 mm rather than 40 mm is a fault, not just slow.
Another name for the site manager. Construction manager is a third. All three can appear in a question and mean the same role.
The briefing every site gives before you start: its rules, its hazards, its access routes and its assembly point. It is the only time you are told them.
Runs the site day to day: who works where, safety, progress and deliveries. Also called site agent or construction manager.
Where progress and problems are raised, and where a clash between trades is flagged before it becomes rework.
The drawing showing the location of the site — where it is, how you get in, where things sit on the ground. Not what is inside the building, which is the scale drawing's job.
A plan made before work starts on a larger project, setting out how waste will be reduced and handled. The regulations requiring one were revoked in England in 2013, but the plan is still widely used and still the name the answer guide wants. The best time to reduce waste is before the material is ordered.
The most common cause of site injuries. Nearly all of them come from mess, so clearing up as you go is a safety job.
A screw head with a single straight slot. The oldest type; the driver slips out of it easily.
Where filtration happens: the water passes down through sand and the fine material is left behind. It follows the settlement tank and comes before chlorination, because filtering is easier once the heavy solids have gone.
A clip the pipe presses into past two jaws until it snaps home. Comes out again if you need it to, which is why it suits a run that may be altered.
Water with few dissolved minerals. Lathers easily and leaves no scale, but is more likely to be slightly acidic and corrode metal.
The vertical 110 mm pipe carrying WC discharge and the branch wastes down to the drain. 110 mm is the odd one out on the size list because it is not really a waste at all — it is soil pipe. Its clip is a much heavier bracket than a basin or bath waste clip, and unmistakable in the identification task.
The panel in a solar thermal system that absorbs heat from the sun and passes it to a fluid, which is pumped to a coil in a hot water cylinder.
Roof panels that turn daylight into electricity. Zero carbon, because nothing is burned. The pair to keep straight is solar thermal, which makes hot water and counts as low carbon — both are panels driven by the sun, and the exam relies on people mixing them up.
Roof panels that absorb heat from the sun and pass it to a coil in a hot water cylinder. Heats water, not the house.
The alloy that fills a capillary joint. In a solder ring fitting it is already inside; with end feed you feed it in yourself.
A capillary fitting with the solder already in a ring inside it. Also called Yorkshire. A complete ring of solder at the mouth shows it has worked.
Heating a capillary joint until solder is drawn into it. You heat the fitting, not the solder: the joint has to be up to temperature to draw the solder in.
A business owned by one person. Simple to set up, and the owner keeps the profit — but is personally responsible for the debts.
A poured concrete floor with no void underneath. One of the two domestic floor types you are asked to name from a picture. You cannot lift it, so pipework goes in a chase or above the floor.
Water's ability to dissolve other substances. It dissolves so much that it is called the universal solvent.
Containing a solvent rather than water. Solvent based glues and paints are hazardous waste, while their water based equivalents are not — so you read the tin rather than the name.
The cement that softens two plastic surfaces so they fuse into one piece. It gives off flammable vapour, so it is kept away from flames and used with ventilation.
A joint made with a cement that softens both surfaces so they fuse into one piece. The strongest and neatest, but permanent.
Solvent weld cement, cleaning fluids and adhesives. They give off vapour, most are flammable, and you usually use them under a sink with no ventilation.
The distance a joist bridges between its supports. Notch and hole zones are given as fractions of it, because bending is greatest in the middle and least near the supports.
A firm that does one specific type of work and nothing else — drainage, lift installation, water treatment, unvented cylinders. The same thing as a specialist firm; the paper uses both wordings, so learn both. They exist because no single firm carries every skill a build needs.
A firm that does one thing well — drainage, lift installation, water treatment — brought in when a job needs something out of the ordinary.
How much energy it takes to raise one kilogram of a substance by one degree. Water has a high one, which is why it is used to carry heat round a building in the first place, and why a cylinder takes a while to reheat.
Checks level and plumb — horizontal and vertical. Used on pipework, radiators and cisterns.
A tap that breaks the flow into a spray, so hands can be washed with far less water.
Water emerging naturally from the ground, already filtered by the rock it passed through.
A plasterboard fixing whose wings spring open behind the board, spreading the load over the back face rather than the crumbly core.
A cut at right angles to the pipe. It matters more on plastic than on copper, because the pipe end seats against the O-ring and is part of the seal.
The SI unit of area, symbol m2. Used for radiator sizing, insulation and underfloor heating layout.
Electricity drawn by equipment left on standby rather than switched off. It draws all day, every day, for nothing.
The legal minimum sick pay. Since 6 April 2026 it is paid from the first day off sick, for up to 28 weeks. Some employers pay more.
Water in its gas state. It occupies about 1600 times the volume of the water it came from, which is why an uncontrolled boiling system is so dangerous.
A chisel for chopping out holes and chases in bricks and blocks. Its fault is a mushroom head, and the maintenance is to grind it away and repair or replace as required. One of the four worked examples the answer guide itself uses, so it is worth knowing in exactly that shape.
Free standing access equipment for short jobs at low height. Checked for sound hinges, unfrayed ropes, level ground, adequate height and undamaged stiles.
The treatment stage where chlorine is added to kill bacteria. This is what makes the water safe to drink.
The two side rails of a ladder or step ladder. Checked for damage, bending and splits before use.
A pipe wrench whose jaws bite harder the more you pull. Two are used together — one to hold, one to turn.
The frame that holds a die and gives the leverage to turn it. Stock holds, die cuts — the two words get muddled and are asked about separately.
Hand tools for cutting a thread. The die is the hardened cutter; the stock is the frame that holds it and gives leverage.
Closes the end of a gutter. An external stop end fits over the outside; an internal one closes it from inside, where the gutter runs tight to a wall.
A valve for mains pressure, with a crutch or lever head. It restricts the flow slightly, which is fine on the main and not on gravity pipework. It is directional, with an arrow on the body.
The long key used to turn the external stop valve, which sits down a covered chamber at the property boundary.
The cold water tank, usually in the loft, that feeds the outlets in an indirect system and supplies the hot water cylinder.
A system with a cold water storage cistern and a hot water cylinder, as opposed to a combination boiler. It gives a reserve of water if the main fails, and lower pressure upstairs.
A fitting that clamps around a soil pipe to let a new branch be cut in where there is no spare socket.
How much load a material carries before it fails.
A line stretched between two points to work to. On a gutter run it sets an even fall from the high end to the outlet, which eyeing it never does.
Makes sure the building will stand up — foundations, beams and loads. Decides what you may and may not cut into.
A vertical timber in a stud wall. Always the first choice for a fixing in plasterboard, because an ordinary plug in the board alone pulls straight out.
The timber frame that forms the internal walls of most modern houses. The uprights in it are the studs, and they are what you fix to when the face is only plasterboard.
A firm brought in by the main contractor to do one part of the job. Most plumbing on a large site is done by a sub contractor.
The third step on the progression route — apprentice, qualified trades person, supervisor, manager, director. The first step into being responsible for other people's work as well as your own.
Rainwater run off from roofs and paving, as opposed to foul water. Guttering and downpipes are a surface water system.
Tracing what is already there before cutting anything in an existing property — the pipework, the stopcock, what feeds what. Existing systems rarely match a drawing.
Another name for the offset bend — the pair of bends stepping a downpipe back to the wall from a gutter that overhangs it.
The metal shavings produced by cutting or threading. Razor sharp, so it is brushed away rather than wiped by hand.
A fitting that connects pipework to the threaded tail of a tap or ballvalve.
The threaded shank a tap connector joins to. Basin and bidet pillar taps have 15 mm tails; bath taps have 22 mm.
Measuring and marking out. Plumbing is marked in millimetres, so a run quoted in metres is converted before it goes on the wall.
A slightly tapered thread, so it tightens as the fitting goes further on. The taper is what lets a screwed joint seal at all.
Two or more people lifting together. One person calls the lift so everybody moves at once, and where it is going is agreed before it is picked up.
A college qualification proving you know the subject, assessed by tests and practical tasks. It sits alongside an NVQ, which proves you can do the job at work.
A fitting that takes a branch off a run.
How much pulling force a material takes before it snaps.
A tap or outlet at the end of the pipework. Regular maintenance of terminal fittings and float valves prevents wasted water.
The employment right covering how a job is ended. Notice runs both ways: you owe at least a week once past a month's service, and your employer owes a week for every complete year worked, up to twelve. Dismissal also has to be for a fair reason and follow a proper procedure.
A plastic that sets hard once formed and cannot be softened again — toilet seats, some handles and casings.
Produces a small voltage that varies with temperature. Used as a temperature sensor, and met again on gas appliances.
Measures temperature — liquid in glass, or digital. It measures without switching anything, unlike a thermostat.
A plastic that softens when heated and can be reshaped — polythene, PVC, ABS, polypropylene.
Measures temperature and switches something on or off. The switching is what makes it a thermostat rather than a thermometer.
Room thermostats, thermostatic radiator valves and programmers, so heating only runs where and when it is wanted.
A radiator valve that closes as the room reaches temperature, so each room is controlled separately. One of the named system controls.
The spiral groove cut onto a steel pipe end so it can screw into a fitting. A good one is clean, sharp, square to the pipe and slightly tapered.
How far a thread is cut. The die is run until the pipe end is flush with its outer face. Too short and the fitting will not reach; too long and bare thread is left showing, which rusts.
Two feet and a hand, or two hands and a foot, kept on a ladder while climbing. It is why you do not climb carrying things.
Electricity generated from the movement of the tide. A zero carbon source.
A bit for drilling through glazed tile, used on slow speed with no hammer action. The wall behind is then drilled with a masonry bit.
A piece of timber fixed between studs before the plasterboard goes on, so there is something solid to screw into later. Five minutes at first fix that saves an hour at second.
Turning up when you said, and ringing ahead if you cannot. The single most common complaint about tradespeople, and almost entirely fixable with a phone call.
The other name for kick boards — the boards around the edge of a working platform that stop tools and materials being kicked off onto people below. Both names are used equally on site.
Boards that interlock along their edges. The tongue must be cut before a board will lift.
A body that supports firms in a trade rather than setting the rules. The ECA is the electrical one; the APHC is the plumbing and heating one.
A lead run across a working area. Both a trip hazard and easily damaged by whatever gets dragged over it.
The yellow box that supplies 110 volt site tools. It is centre-tapped to earth, so the maximum shock voltage is about 55 volts rather than 230.
The bend under an appliance that holds a small amount of water. That water is the seal stopping drain smells coming back into the room.
The water standing in a trap. Lose it — through siphonage or evaporation — and the room smells of drains.
Offcuts, tools, packaging, and above all trailing leads and hoses. An extension lead across a walkway is the most common trip on any site.
Sunlight breaking plastic down and making it brittle. It is why plastic pressure pipe must not be run where daylight reaches it over time.
A three-part fitting that lets threaded pipework be taken apart in the middle without unscrewing the whole run.
Joins two lengths of gutter and supports the joint at the same time.
What water is called because it dissolves so much. It is why water picks up minerals from the ground and metals from pipework, and the root of hardness, scale and corrosion alike.
No separation in law between the person and the business, so the owner is personally responsible for its debts. Sole traders and partnerships both carry it.
Work that happens because something has already failed: burst pipes, running overflows, dripping taps and blockages.
Rainwater collected off high ground into a reservoir. Little contamination, because few people live there.
Telling the customer what a fitting does and how to use it. A named method of reducing water waste, not an optional courtesy.
Fumes given off by solvents, soldering flux and paint. Harmful to breathe, and easy to ignore because there is no immediate effect.
A hazard from SDS drills, breakers and grinders. Causes lasting nerve damage to the hands.
Treating somebody badly because they complained about discrimination. It is unlawful in its own right, separate from the original complaint.
A sheet floor finish, often stuck down. It rarely goes back looking the same, so the customer is warned before you start rather than afterwards.
Looking a tool over before every use — not every week. It catches most of what turns a power tool into an electric shock.
A plastic plug that expands in a drilled hole in masonry so a screw can grip.
The overflow from a cistern, discharging outside where it will be noticed. Water running from it means a float valve has failed.
The registration anyone carrying waste as part of a business must hold. Check for it before paying someone to take waste away.
Sized to the pipe — 32, 40 or 110 mm. Too big and the pipe moves; forced on too tight and it cannot expand.
The document recording a transfer of waste from one holder to another. It is your evidence that you met the duty of care.
Responsible for water resources and uses, quality of service, infrastructure, water supply and sanitation. They supply the water and take the waste away.
Using water as the carrier rather than a solvent. Water based glues and paints count as non-hazardous waste.
Reducing how much water a household uses. It matters because water has to be collected, treated, pumped and treated again, and a metered household pays for every litre twice.
The endless recycling of water: evaporation from the sea, condensation into cloud, rain, run-off to rivers and back to the sea.
Red label. Use on class A only. Never on electrical or on flammable liquids, because water conducts and spreads them.
A bang in the pipework when the flow stops suddenly and loose pipe strikes the structure. Cured by identifying and refixing the loose pipework.
The pipe in the street carrying treated water out to properties. Last of the seven labels on the supply diagram, and the point where the water authority's pipework ends and the customer's begins.
The service reservoir held high so gravity does the distribution. It matters more than it looks: water has no pump behind it once it leaves, so the height of the tower is the pressure at your customer's tap.
A float that has taken in water and sits low, so the valve never closes and the cistern overflows. A common cause of an overflow where the valve itself seems to work.
The unit of power — the rate at which energy is used or delivered. Boiler and radiator outputs are quoted in kilowatts, which is a thousand watts.
Waste Electrical and Electronic Equipment regulations. Cover motors, control equipment, lamps, printed circuit boards and drills, keeping them out of landfill.
The ordinary facilities needed to work decently — toilets, washing facilities, drinking water, somewhere to change and somewhere to eat. A legal duty, not a courtesy.
Yellow label. For cooking oils.
Water that has been treated and tested and is fit to drink.
Electricity generated from the wind. A zero carbon source.
Blades driven by the wind turning a generator to make electricity. Domestic ones are small and depend entirely on an exposed, genuinely windy site.
Used with a cleaning brush to clean the pipe end and the inside of the fitting until bright. Solder will not flow onto dirty or oxidised copper.
The electrical standards, published by the IET. The book every electrician works to.
An account of what you saw, given as part of reporting an accident. The third step after telling your supervisor and completing the accident book.
A bit for larger holes in timber. Flat bits and auger bits are the two kinds; a flat bit is how most joists get drilled for pipe.
Cuts and shapes timber — notching a joist, letting in a fixing. One of three chisels for three materials.
Compressed wood fed automatically into a biomass boiler. The pellet is the giveaway word in the exam: asked which installation provides heat from wood pellets, the answer is biomass, not a heat pump and not solar.
Cuts timber. Too coarse for plastic pipe, which needs a fine toothed saw to cut cleanly.
The plan of who is working where and when. Following it means your work fits between everyone else's.
The document saying when each part of the job happens and who is on site when.
Any work where a fall could injure you — not only high up. A fall from a step ladder onto a concrete floor counts. Falls are the biggest killer in construction.
The employment right capping the working week at 48 hours, averaged over 17 weeks. You may opt out, but only in writing, and nobody can make you. The averaging is why one long week is not automatically a breach.
Sources that release no carbon in use: wind, tidal, hydroelectricity and solar photovoltaic.
Try a different word, or check the spelling.
The Level 1 course takes every one of these terms and drills it — lesson quizzes, key facts, flashcards, AI-marked short answers and interactive tasks, with anything you get wrong coming back until it sticks.
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