Safe handling practices

Safe handling practices

1. What Safe Handling Practices Are (Electrical Safety Culture)

Safe handling practices = rules and habits to prevent electric shock, burns, fire, and equipment damage when working on or near live or potentially live circuits.

2. Core Practices (exam list — 8 with one-line)

Practice	Detail
1. Assume all conductors are live until tested and proven dead (verify with tester)	Never touch bare conductor
2. De-energize and isolate	Switch off, lockout-tagout (LOTO), remove fuse, discharge capacitors
3. Use insulated tools and PPE	Insulated screwdrivers, gloves, shoes, mat, no metal jewellery
4. One hand rule (when possible)	Keep one hand in pocket when probing high voltage to avoid hand-to-hand current through heart
5. Dry conditions	No water/moisture, dry hands, stand on dry insulating mat (water ↓ resistance, ↑ shock)
6. Proper earthing and double insulation	Ensure metal bodies earthed, use double-insulated tools
7. Correct rating and fusing	Use right fuse/MCB, proper wire gauge, no bypassing protection
8. No overloading, good housekeeping	Avoid daisy-chaining, no exposed joints, keep cables not under stress, label circuits

3. Why Each Matters (physiology)

• Current through body: 10 mA tingling, 20 mA cannot let go, 50 mA respiratory paralysis, 100 mA ventricular fibrillation (lethal) — voltage not directly lethal, current is, and $I=V/R_{body}$ where $R_{body}$ drops from ~100kΩ dry to ~1kΩ wet ⇒ wet doubles danger.

4. Worked Illustration

Need to replace plug: Switch off at MCB, test with tester, use insulated screwdriver, keep dry.

Working on 230V panel: wear gloves, stand on rubber mat, use one hand, keep other insulated.

If shock occurs: do not touch victim with bare hands, switch off or use insulated stick to separate.

5. Exam Points

• List 6–8 safe handling practices — 5-7 marks, very frequent (the most common safety question).
• Mention LOTO, insulated tools, dry conditions, one-hand rule — 5 marks, frequent.
• Explain why current not voltage kills and $R_{body}$ wet vs dry — 3-5 marks, frequent.
• Show first aid: switch off before touching victim — 3 marks.