Job-Site Safety, Tools, and Installation Practices
What this domain tests
Job-site safety and installation practice are tested through scenarios: lockout/tagout, test-before-touch, PPE, ladder use, tool selection, cable support, and firestopping. The exam expects OSHA-style safe work habits, not just code knowledge.
Core rules
- De-energize and lock out before working on circuits; verify with a tester on a known live source, then on the circuit. Treat non-contact testers as a supplement, not proof of de-energization.
- Use PPE and insulated tools rated for the voltage; inspect cords, ladders, and testers before use.
- Keep ladders on stable surfaces, maintain the 4-to-1 angle, and do not stand on the top step.
- Support cables per the wiring method and manufacturer; firestop penetrations in rated assemblies.
- Use GFCI protection for temporary power and follow confined-space and fall-protection rules.
Worked example
A technician opens a 120 V control cabinet to add a 24 V Class 2 cable. The safe sequence is: shut off the branch circuit, apply lockout/tagout, verify the tester on a known live source, verify zero voltage at the cabinet, then work. The Class 2 cable still needs separation from power and firestopping at the penetration.
Traps
- Relying only on a non-contact voltage tester.
- Leaving a cabinet energized because the work is just low voltage.
- Skipping firestopping in a rated wall.
- Using the top step of a ladder or an unrated ladder near electrical work.