Workplace Communication, Safety, and Housekeeping
Domain 1 tests the shop-floor layer of the trade: how a technician receives and documents work, controls hazards, and keeps the bay under 5S. Items typically cover PPE selection, the hierarchy of controls, waste segregation and labelling, fire-extinguisher classes, lockout/tagout, SDS interpretation, and repair-order recording.
Core rules
- 5S: Seiri (sort), Seiton (set in order), Seiso (shine), Seiketsu (standardise), Shitsuke (sustain) - the exam asks what each step adds, not just the words.
- Apply the hierarchy of control in order: elimination, substitution, engineering control (local exhaust at the tailpipe, welding fume extractor), administrative control, and PPE last.
- PPE follows the hazard: nitrile gloves for solvents, leather for welding and hot metal, respirator or dust mask for brake dust, safety glasses and face shield for grinding and compressed air.
- Chock the wheels and support the vehicle on stands on a level floor; a jack is a lifting device, not a support.
- Segregate waste at source and label containers: used oil, filters, batteries, coolant and solvent are separate streams; never pour coolant or brake fluid into drains.
- Read the SDS: Section 2 gives hazards, Section 4 first aid, Section 8 exposure limits.
Worked example
A technician is about to crack open a fuel line on a gasoline engine; the bay holds a water (Class A) extinguisher and a CO2 unit. Reasoning: gasoline is a Class B flammable liquid, so water spreads it rather than smothering it. CO2 is rated for Class B and C (energised electrical) and leaves no powder residue in a fuel system. Control the hazard first - remove ignition sources, keep the extinguisher within reach, and wear eye protection while fuel pressure is relieved. The correct answer is the CO2 unit plus elimination of ignition sources, not the water extinguisher.
Traps
- Treating an ABC extinguisher as universal; it does not cover Class D combustible metals or Class K cooking oil.
- Blowing brake dust out with compressed air instead of a wet method or extraction.
- Signing a repair order without documenting the complaint, diagnosis, parts fitted and customer approval for added work.
- Storing gas cylinders horizontally or without a valve cap.