5 Slight shock, not painful. (Average individual can let go) 6 – 25 (Women) Painful shock (Muscular control lost). 9 – 30 (Men) ‘Let-go’ range. (Freezing current) 50 – 150 Extreme pain, severe muscular contractions, (Person may be thrown away), respiratory arrest. 1,000 – 4,300 Ventricular fibrillation (Rhythmic pumping of heart ceases) - Muscular contraction and nerve damage - Death most likely. > 10,000 Cardiac arrest, severe burns. - Probable death. Note: Low voltage does not imply low hazard 27
Injuries associated with electrical hazards. • Shock • Burns • Blood clots • Nerve damage • Falls 28
Types of Burns Caused by Electricity Electrical bur ns (from electric current flowing through body tissues) Arc (flash) burns (high temp near body, explosion) Thermal contact burns : from overheated conductors or ignited clothing. • (All three types can occur simultaneously) 29
Some causes of electrical accidents 1. Failure to comply with safety rules 2. Incomplete/wrong isolation, 3. Failure to test isolated lines or use of wrong testing methods 4. Failure to identify the isolated equipment 5. Inadequately secured dangerous workplaces 6. Ignorance or lack of information or Carelessness 7. Breaching of safety clearances (lines and substations) 8. Incompetent people being left in-charge 9. Unauthorized or unprocedural activities 10.Failure to use appropriate PPE 11.Inadequate, unsuitable tools or poorly maintained tools
SAFETY IN ELECTRICAL WORK Proper Work Planning Tool Box Talks / “Kupanga Kazi” Proper Tools & Equipment Inspection of Tools & Equipment Adequate Isolation Testing (Live-Line Testers) Earthing ( CME ) Permit to Work (PTW) Other Precautions ( Lock-Out/Tag- Out/Test-Out) - LOTOTO ) Effective communication (use of Radio Call) Use of appropriate PPE
Preventing Electrical Hazards • Insulation + Colour coding • Guarding • Grounding & use of Circuit Protection Devices • Safe work practices + using suitable equipment • Testing ‘suspect’ cables/equipment • Training, • Complying with the relevant Statutory requirements • Electrical installation by qualified personne l 35
Some Electrical Safe Work Practices • De-energizing ( Lock-Out/Tag-Out/Test Out ) electric equipment before inspecting or making repairs. • Using tools that are in good repair (never use defective tools.) • Using proper plugs (avoid poking naked wires into sockets) • Using good judgement when working near energized lines or overhead lines. • Observing HV line Clearances • Using good/proper and neat wiring techniques • Adhering to Electrical Safety Rules. • Using appropriate personal protective equipment (PPE). 36
Personal Protective Equipment (PPE) • Safety Helmets (also with face shield) • Hand-Gloves (Rubber, Leather, PVC, Latex) • Sleeves (PVC, Rubber) • Safety boots/shoes (Acid/Oil proof, Anti-static, steel toe-cap, treaded sole) • Overalls, dust coats • Safety Belts, Climbing irons • Ladders (Wooden, Plastic, Fibre-glass) • Rubber Mats 37
POLES SAFETY Poles related accidents arise from : 1.
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- Spring '18
- Professor Obura Oluoch
- Occupational safety and health, safety officer, Safety Engineer, Directorate of Occupational Safety and Health Services, General Occupational Safety and Health, Safety Competency & Authorization