ABSTRACT
Outline the principles, hazards and risks associated with the use of electricity in the workplace ■ Outline the control measures that should be taken when working with electrical systems or using electrical equipment ■ Outline the control measures to be taken when working near or underneath overhead power lines ■
The basic electrical principles and defi nitions … The causes and treatment of electric shock … Other electrical hazards and injuries and their associated controls … The selection, suitability, maintenance and inspection of electrical equipment … The advantages and limitations of protective systems … The hazards and controls associated with overhead electrical services … The application, advantages and limitations of portable electrical appliance testing … HAZARDS AND RISKS ASSOCIATED WITH THE USE OF ELECTRICITY
ELECTRICAL PRINCIPLES AND DEFINITIONS
■ voltage (volts V)
■ current (amps A)
■ resistance (ohms 1)
■ Ohm’s law – V = I × R
■ Power P = V × I Watts
■ conductors – electricity will fl ow easily
■ insulators – very poor conductors
■ earthing – connection to earth
■ short circuit – direct fl ow to earth
■ low voltage – not exceeding 600 V
■ high voltage – exceeding 600 V
■ mains voltage – 220/240 V.
