Safety Talk Portable Electrical Equipment Sheet 1 Electricity

Safety Talk - Portable Electrical Equipment Sheet 1 - Electricity The flow of electricity is like the flow of water in a pipe. Resistance Pressure Flow Current is similar to the total volume of water flowing past a given point in a pipe, in a given length of time. Electrical flow is measured in Amperes. Voltage is like the water pressure in a pipeline. Electrical equipment powered by 440 volts or less is “low voltage”. Resistance is anything that resists the flow of electricity which is similar to how the friction from a pipe restricts the water flow. Resistance is measured in Ohms. The rate of electrical current depends upon the voltage and resistance. TRAINING NATIONAL

Safety Talk - Portable Electrical Equipment Sheet 2 - Effects of electrical current flow 10 milli. Amps - muscular contractions making it difficult to release grip on the electrical conductor. 20 milli. Amps - severe muscular contractions making it difficult to breathe. 50 milli. Amps - severe breathing difficulties or breathing stopped. 70 to 200 milli. Amps - erratic heart motion resulting in loss of blood circulation. 400 milli. Amps - burns at the entry and exit points of the electrical current flow path. TRAINING NATIONAL

Safety Talk - Portable Electrical Equipment Sheet 3 - Checking portable electrical equipment Always check for: • cracks in the insulation casing; • loose or missing casing screws; • splits or damage to the power cord insulation; • exposed wires; • loose connection between the power cord and the tool; • bent or missing plug pins; and • cracks in the plug. TRAINING NATIONAL

Safety Talk - Portable Electrical Equipment Sheet 4 - Double insulated power tools Non-conductive, shatter proof outer casing Double Insulated symbol Double insulation protects the user from electrical shock if interior wiring contacts the outer casing but it does not provide total protection from electric shock because: • immersion of the tool in water can allow an earth leakage; and • double insulation does not protect against any defects in the cord, plug or power outlet. TRAINING NATIONAL

Safety Talk - Portable Electrical Equipment Sheet 5 - Electrical inspection tags Each portable electrical tool should be fitted with a current inspection tag. COMPLETE WHERE APPLICABLE Owner Test Date Equipment type Licence Number Plant Number Signature PLEASE INFORM YOUR ELECTRICAL SERVICES IF THIS APPLIANCE IS DEFECTIVE IN ANY WAY TRAINING NATIONAL RED: January to March GREEN: April to June BLUE: July to September YELLOW: October to December

Safety Talk - Portable Electrical Equipment Sheet 6 - Residual current devices If a fault causes electricity to flow to earth, the Residual Current Device will disconnect the electricity supply, avoiding the risk of a fatal shock. They disconnect the electricity supply at a level of 30 milli. Amps It will disconnect within 10 -15 milliseconds. RCD If you are unsure if the power outlet you are going to use has built in earth leakage protection, use a portable Residual Current Device. TRAINING NATIONAL Power Outlet

Safety Talk - Portable Electrical Equipment Sheet 7 - Using Portable Electrical Equipment You should never: • kink the power cord; • allow power cords to contact water, oil, steam or dampness; • leave power tools switched on at the power source when not being used; • handle electrical equipment with wet hands, in high humidity or outdoors after a rain storm; or • disconnect a power tool without first switching off the electricity at the power outlet. Position power cords and extension leads so they will not become a trip hazard for other people. Fully unwind extension cords from storage reels before energising them. TRAINING NATIONAL