Electrical Safety Module 2 PDF

ELECTRICAL SAFETY BASIC ELECTRICAL ENGINEERING (ELEN 016) PROFESSOR: ENGR. JOMAR J. DACLES, REE, RME, S02 LEARNING OUTCOMES: 1. Acknowledge and identify the electrical hazards and effects of electricity to human body 2. Apply the different ways to protect oneself from the dangers...

ELECTRICAL SAFETY BASIC ELECTRICAL ENGINEERING (ELEN 016) PROFESSOR: ENGR. JOMAR J. DACLES, REE, RME, S02 LEARNING OUTCOMES: 1. Acknowledge and identify the electrical hazards and effects of electricity to human body 2. Apply the different ways to protect oneself from the dangers of electricity 3. Be able to perform Lockout/Tagout ELECTRICITY AND IT’S KIND Is composed of the simplest form of matter, the electron. The electrons spin around the nucleus of an atom are easily broken away when sent to a circuit, we have electrical system. ELECTRICAL HAZARD Can be defined as a serious workplace hazard that exposed workers to burns, electrocution, shock, arc flash or arc blast, fire, or explosion. WHERE DO ELECTRICAL ACCIDENTS USUALLY OCCUR? WHY LOW VOLTAGE ?  2 TYPES OF ELECTRICAL HAZARD 1. Physical Hazard - are factors or conditions within the environment that can harm your health. Slippery floor (Water) Exposed Wiring Overloaded Circuits Electrical Cord (Located in water) Energized Equipment with Exposed Circuit PHYSICAL HAZARD VIDEO  CONT. 2. Behavioral Hazards- Is when a person, by the way they act or behave, poses a threat for electrical accident. Doesn’t have care “thuglife” Lack of knowledge Working while stressed Taking shortcuts or risk BEHAVIORAL HAZARD VIDEO  ELECTRICAL SHOCK An electrical shock is received when electrical current passes through the body. Typical point of entry is hand and foot while they are contacted with the electricity. You will get an electrical shock if a part of your body completes an electrical circuit by… 1. Line to Ground 2. Line to Line FLOW OF CURRENT IN BODY FAQ: WHY BIRDS DON'T GET ELECTROCUTED ON POWER LINES?  INNER RESISTANCE OF HUMAN BODY 500-1000 Ohms (Dry) 300 Ohms (Wet) Note: Skin resistance is greatly depends on moisture content Sweaty Skin (“Pasma”) – Less than 1/12 of your skin resistance.  FLOW OF CURRENT THROUGH THE BODY DEPENDS UPON. ❑ Voltage of the circuit ❑ Insulating quality of the place ❑ Resistance of the skin ❑ Area of contact ❑ Pressure of Contact  EFFECT OF CURRENT IN HUMAN BODY ❑ 8 – 15 mA - Pain ❑ 15 – 20 mA - Pain, Loss of Muscular Control ❑ 20 – 100 mA – Intense pain and paralysis of breathing muscles and possible suffocation ❑ 100 – 200 mA – Ventricular fibrillation which will cause death ❑ >200 mA (at 220v) – Heart movement stops (recovery possible if treated in 3 minutes), Burn also occur.  EX. SCENARIO AT HOUSEHOLD WITH 220V 220 Volts 1000 Ohms =.22 Ampere THE MAIN HAZARDS WITH ELECTRICITY Contact with live parts causing shock and burns. Faults which could cause fires. Fire or explosion where electricity could be the source of ignition in a potentially flammable or explosive atmosphere. CLUES THAT ELECTRICAL HAZARDS EXIST Tripped circuit breakers or blown fuses. Warm tools, wires, cords, connection, or junction boxes. Circuit breaker that shuts off a circuit Worn or frayed insulation around wire or connection ELECTRICITY AND WATER The likelihood of being shocked is greatly multiplied in damp locations. People are excellent conductors Never use electrical equipment in damp or wet ares. Do not spray water around any electrical source ELECTRICAL FIRE HAZARD Electricity is one of the most common causes of fire both in the home and in the workplace. Electric short circuiting, arcing, sparks, overloading, use of defective or misused electrical equipment are major causs of electrical fires. SHOCK IS THE MOST SERIOUS ELECTRICAL HAZARD This happens when you touch a live wire, a tool or a machine with poor insulation. You then become a conductor. The shock that you feel is the electrical current going through your body. SHOCK may cause: Pain Loss of muscle control and coordination Internal Bleeding Nerve, muscle or tissue damage Cardiac arrest or Death CONTROL MEASURE CLASS C FIRE PERSONAL PROTECTIVE EQUIPMENT (PPE) PREVENTING ELECTRICAL SHOCKS Use only electrical equipment or devices that are “good” condition. - Clean and Dry - Intact, no cracks or holes in the case - Power cord is in good condition No worn spots or crack insulation -Regularly inspected FOLLOWING SAFETY PRACTICES Use electrical equipment as it was intended to be used. Follow manufactures recommendations Follow all site safe practices AVOID AND REPORT HAZARDS Stay away from the hazard Take steps to keep others away Report hazard GROUND FAULT CIRCUIT INTERRUPTER (GFCI) Protects you from shock Detects difference in current between the black and white wires If ground fault detected, GFCI shuts off electricity in 1/40th of a second Use GFCI’s on all 240-volt, single-phase, 15- and 20- ampere receptacles, or have an assured equipment grounding conductor program. HOW GFCI WORKS LOCK OUT TAG OUT TRY OUT (LOTOTO) The standard procedure for the control of hazardous energy sources which cover maintenance of machines in unexpected start-up of machines or release of stored energy could cause injury to employees.  6 STEPS OF LOTOTO 1. PREPARATION – know the equipment and its energy source before working on it. 2. SHUTDOWN – turn off the equipment 3. ISOLATION – find and isolate every form of energy that the machine uses. This includes pulling fuses, throwing disconnects and capping any secondary sources of energy. 4. APPLICATION – anything that might restore the flow of energy to the work area must be locked out. In situations where multiple pieces of equipment are being locked, an authorized employee places all keys in a lock box to which each employee attaches his or her personal lock. 5. CONTROL – even after equipment is locked out, you must control stored energy. 6. VERIFY - Energy source is shut down, blocked off, controlled, and locked out VIDEO LOCK OUT TAG OUT TRY OUT VIDEO LOCK OUT TAG OUT TRY OUT ACTIVITY 2: FINDING ELEC. HAZARDS AT HOME List Down at least 5 electrical hazard at your home, then write the harm or possible effect of it and your proposed control measure. HAZARD EFFECT CONTROL Prepared By: Engr. JOMAR J. DACLES