Containment
The system that carries or encloses wiring along its route, such as conduit, trunking, tray or basket. It helps support and protect cables and keeps runs organised for installation and maintenance. The material and fixing method must suit the location and the cables; containment alone does not prove a circuit safe.
Using Containment in context
Updated
A distinction worth remembering
Containment supports or protects wiring, but different systems suit different conditions. Mechanical protection, corrosion, access and any protective-conductor function need separate consideration.
Questions to take further
- How can I revise Containment beyond the definition?
- Explain what Containment describes, compare it with a related term and use it in a topic question. State any assumptions and what evidence you would need before applying the idea to real work.
Sources
- IET: current BS 7671 edition and updates — BS 7671:2018+A4:2026 and the main subject areas updated by Amendment 4.
- IET: earthing and bonding FAQs — Protective bonding, earthing arrangements and loop impedance.
Where Containment fits in the learning path
The Installation section covers these units:
- Wiring Systems & Enclosures
- Cable Selection & Circuit Design
- Earthing, Bonding & Consumer Units
Curriculum mapping: C&G 2365 Units 203/204/305.
See this section in the full curriculum
This section is on the Plus path. Lesson availability depends on content review and your learning path.
Read, practise, return
1. Read it in context
- Cable SizingInstallation
- Consumer UnitsInstallation
2. Try recalling, then explore practice
Use the memory prompt below to connect the vocabulary.
- Cable Selection — quiz previewPlus · Installation
3. Return to the meaning
After reading or practising, explain the idea in your own words, then check what you remembered.
Recall a related term
Which term fits this definition? Say it to yourself, then reveal it. This is a memory prompt, with no score or saved result.
A cable with steel wires around its cores to give mechanical protection, often selected for outdoor or underground routes. The armour may serve as a protective conductor only when the whole design, glands and connections make a suitable continuous path. SWA names the cable construction, not permission to bury it without a route assessment.
Compare related terms
Open a meaning to compare its role with Containment, or follow its full entry.
SWA — Steel Wire Armoured
A cable with steel wires around its cores to give mechanical protection, often selected for outdoor or underground routes. The armour may serve as a protective conductor only when the whole design, glands and connections make a suitable continuous path. SWA names the cable construction, not permission to bury it without a route assessment.
Read the SWA entryCurrent-carrying capacity — Iz
The current a conductor can carry continuously under stated installation conditions without exceeding its specified temperature limit. Cable tables give values for defined reference conditions, with adjustments where the actual conditions differ. Meeting the thermal-capacity check does not replace the other design checks, including protective-device coordination, voltage drop and fault protection.
Read the Current-carrying capacity entryVoltage drop
The reduction in voltage along a current-carrying circuit caused by its impedance. Load current, conductor size, length and, in AC circuits, reactance and power factor can affect it. Equipment must receive a suitable voltage, so voltage-drop requirements are checked separately from a cable's thermal current rating.
Read the Voltage drop entryA definition is a start. Using it in a real question is where it sticks.