Electrical Industrial Safety Presentation

Presentation on basics of Electrical Safety

1. ELECTRICAL SAFETY DINESH M ENGINEER (Opn)

2. Introduction Electricity is a part of every day life at home and at work. At home electricity is used for everything from showers to Cooking At work, it powers Computers, tools and many major equipment. Industrial facilities are equipped with a wide range of Single- Phase and three phase electrical equipment Sample Footer Text 2/8/20XX 2

3. OBJECTIVES DEFINE IMPORTANT TERMS RELATED TO SAFETY DESCRIBE THE DIFFERENT TYPES OF INJURIES CAUSED BY ELECTRICAL SHOCK INDENTIFY SHOCK PROTECTION BOUNDARIES AND THE CURRENT LEVELS THAT CAUSE ELECTROCUTION SAFE ELCTRICAL WORK PRACTISES AND WORK CONDITIONS IDENTIFY ELECTRICAL SAFETY WARNING SIGNS AND LABELS PURPOSE OF INSTALLING PROTECTIVE GROUNDS 3

4. WHAT IS AN ELECTRIC SHOCK? Electric shock is a risk everytime we use anything powered by electricity At work the risk is greater due to the number of power tools, electrical circuits used.

5. RED/YELLOW/BLUE- This wire is always connected at the other end to the voltage source. PARTS OF WIRING 5 Neutral Wire- It is path for current to flow back to the source Ground Wire- It provides an alternative path for electricity back to the source in the event of a fault

6. Simple Closed Circuit Sample Footer Text 2/8/20XX 6

7. 5mA of current through a human body may cause injuries Effects of Electricity on Human Body 7 17 to 99mA current is sufficient to cause death to a Human Our Home appliances current ranges from 15 to 30 amps – almost 1000 times greater than what can be hazardous

8. Basic Electrical Theory Any Condition that reduces the resistance to current flow through a person’s body increases the risk of electric shock Current flows in the path of least resistance to the point of lower voltage A Shock Occurs when there is simultaneous contact with an electrical Source and an object at a different Voltage than the Source During a shock the body become part of a circuit. Break the circuit to stop the shock Wire- Ground Surface shock accidents are more common and difficult to predict 8

9. Common Shock Mechanisms Head/Hand to Foot Shocks Occurs when standing on a grounded surface and the head/hand touches an energised part- Often Occurs while working in tight spaces or near overhead power lines 9

10. 10 2. Foot to Foot (Step Potential) Step Potential Occurs when Voltage under one foot is different than the voltage under the other foot A fallen Power line energises the ground As the distance from the point of contact increases, the voltage decrease

11. 11 3. Hand to Hand/Hand to Elbow Hand to Hand or hand to elbow shock could occur when a person touches a live conductor with one hand, while the other hand or elbow is pressed up against an object that’s connected to the ground

12. SEVERITY Electric Shock severity depends on Amount of Current Duration of Current 100mA for 2 seconds can cause death 1mA- Faint tingle 5mA- Slight Shock >5mA- Possible injury 75mA- Heart failure & Death 12

13. 13 Types of Injury Cell Damage- This happens with current as low as 5mA Burns- Most Common. As the amount of Current increases, the energy absorbed by cells increases to the point that the cells are burned Heart Fibrillation- Can cause death if not treated immediately Secondary Injury- Reactions to Shock

14. Role of Rescuer Should never touch the electrocuted person with bare hands Shut Down the Power source before attempting to rescue the person An unconscious shock victim without a heart beat may need immediate CPR Conscious Person should visit a Physician, no matter how minor the shock maybe 14

15. Arc Flash Arc Flash Occurs when a fault causes a high-current flow to the ground. This results in a bright, high-energy arc and an explosive reaction. Unprotected workers without the use of an Arc Suit can be severely injured from high heat and blast effects. Arc flash typically occurs only around 400 V and above 15

16. SAFETY/CAUTION Electrical workers must be constantly aware of the possibility of contact with energized circuits Untrained workers should not be allowed to Work on energised electrical equipment Electrical Workers Should be trained and Competent in use of PPE, arc-flash protection, insulating/shielding material, insulated tools and test equipment Non Qualified employees should not be allowed to work on energised equipment 16

17. 4 step model for Electrical Hazards 17

18. Identify Hazards- Identify all electrical sources/Power Equipment (Energized Equipment, Power tools, Cords, OH lines, Wet/Damp Conditions) Evaluate Hazards- Reveals the risk electricity present in the work area (Damaged Insulation, Connectors, plugs, grounding of Power tools, Neutral, Overload) Control Hazards- Controlling includes steps to ensure that workers are not harmed when they work near electricity (PPE, repairing damaged insulation, tools) Evaluating Controls- Reviewing all hazard controls are effective(Observations, Periodical Inspection) 18

19. Approach to Minimize Electrical Hazards Determine the level of risk of Shock- Voltage & Distance Ensure safe distance from all energized conductors No Electrical panels(MCC) should be Open. If Open, electrical protection boundaries must be established. Arc flash Boundary must be provided where voltage is greater than 50V 19

20. Warnings/Labels Electrical equipment is typically labelled to Warn Workers of Electrical Hazards and provide information about PPE Exposed Energized equipment should have warning barriers Barriers can include Tape, Rope, Signs, Locked Doors Arc Flash Boundaries are further away from Shock protection boundaries 20

21. Specific Safety Measures Switching and grounding of High Voltage equipment should be done by qualified personnel only In a construction site, all underground and overhead lines should be identified before work begins FR(Flame resistant) clothing should be provided to Electrical workers HV Gloves, Arc rated face shield, safety glasses and all other PPE to be ensured before start of work Use Only Class C fire extinguisher for electrical fires Proper grounding of all electrical equipment to be ensured Pre work briefing should be made mandatory All electrical equipment is live until verified by a Qualified Employee 21

22. Thank You 22