Tools, Materials and Safety: Matching the Tool to the Task
What this domain tests
This domain covers the hand and power tools a plumber uses daily, how to match a tool to a pipe or fitting, and how to identify materials without confusing them. Safety is tested as part of tool use, not as a separate afterthought.
Core rules and concepts
- Use a pipe wrench for threaded steel pipe; its serrated jaws grip and turn. Do not use it on chrome-plated or plastic fittings.
- A basin wrench reaches the nuts behind a wash basin where an adjustable wrench cannot.
- A tube cutter gives a square, burr-free end on copper and plastic; deburr before jointing.
- Threading dies cut BSP threads on GI pipe; use cutting oil and reverse to clear chips.
- Solvent cement is for PVC and CPVC; it is not a thread sealant.
- PTFE tape is wound clockwise on male threads, not on plastic solvent joints.
- Identify plastics by marking: PVC-U for drainage, CPVC for hot water, PPR for hot and cold water, HDPE for buried supply.
- PPE: safety glasses when cutting, gloves for solvents, and ventilation when using cement.
Worked example
A chrome bottle trap under a wash basin leaks at the nut. The gap is 60 mm behind the bowl. An adjustable wrench slips and a pipe wrench would crush the chrome. The correct choice is a basin wrench: its spring-loaded jaw reaches the nut and applies torque without side load. After tightening, wrap the joint with PTFE only if it is a threaded metal joint; do not put PTFE on the plastic compression olive.
Traps that cost marks
- Using a pipe wrench on plastic or chrome.
- Over-tightening a compression nut and splitting the olive.
- Cutting PPR with a hacksaw and leaving burrs.
- Using solvent cement on a threaded joint.
- Choosing GI where CPVC is required for hot water.