General Electrical Knowledge and Work Practices / Safety
Safety questions test whether you work to a procedure, not whether you memorize slogans. Know the hierarchy: eliminate the hazard, then isolate it, then protect the worker.
Concepts to master
- Lockout/tagout: identify all energy sources (including control power, capacitors, back-feeds, generators), isolate, lock, tag, verify. Each worker applies a personal lock; only the person who applied a lock removes it.
- Test-before-touch: verify the tester on a known live source, test the conductor, re-verify the tester.
- Shock and arc-flash protection: approach boundaries, incident-energy ratings on labels, correct PPE and insulated tools, no energized work unless justified and permitted.
- Temporary wiring, extension cords, GFCI protection on construction sites, and cord inspection.
- Ladders, scaffolds, fall protection, confined spaces, and hazardous-location entry rules.
- Worker rights and duties under occupational health and safety law, plus WHMIS/safety data sheets for chemicals.
Traps in questions
The common wrong answer is the fast one: working live because it is quicker, relying on someone else's lock, assuming a circuit is dead because a switch is off, or assuming a breaker labelled correctly protects the right circuit. Another trap is treating a GFCI as personal protection against all shock-it protects against ground-fault current, not line-to-line contact. Also watch for questions where the correct answer is "stop work and report."
Rule of thumb
If a procedure question offers a choice between a shortcut and a documented step, the documented step is nearly always correct. Verify absence of voltage at the point of work, not at the panel.