NFPA 70E Electrically Safe Work Condition: The Exact Sequence That Matters

Regulation: NFPA 70E Article 120

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Steps

1. Identify all sources — Determine all possible sources of electrical energy including backfeed sources.
2. Interrupt load current — Open the load before operating the disconnecting means — do not open disconnects under load unless rated for it.
3. Open disconnecting means — Open all disconnecting means for each energy source.
4. Release stored energy — Release or block stored electrical energy (capacitors, inductors, breaker mechanism springs).
5. Apply LOTO devices — Apply lockout/tagout devices to each disconnecting means.
6. Verify absence of voltage — Use a properly rated test instrument to verify absence of voltage. Test the tester, test the circuit, test the tester again.

Core Concepts

• Electrically Safe Work Condition (ESWC): Achieved when all energy sources are isolated, locked out, and voltage absence is verified. Work within an ESWC does not require arc flash PPE.
• Test-Before-Touch Rule: Before touching any conductor or circuit part, a qualified person must verify absence of voltage with a properly rated, functioning test instrument.
• Qualified Person: Trained and knowledgeable in the construction and operation of electrical equipment and the hazards involved. Qualification is task-specific.

Exam Traps

• ESWC is not achieved until voltage absence is VERIFIED — isolation and lockout alone do not complete the process.
• Test the tester before and after testing the circuit — a failed meter could give a false zero-voltage reading.
• Backfeed sources (capacitor banks, UPS, co-generation) must be identified and isolated.
• Working on de-energized equipment still requires LOTO — ESWC is not just turning it off.
• NFPA 70E applies to electrical hazards in the workplace broadly — not limited to facilities covered by OSHA 1910.269.

Memory Aid

Identify → Interrupt load → Open disconnects → Release stored energy → Lock/Tag → Verify voltage absent. Never skip the last step.