5.1 Principles, Hazards and risks associated with the use of electricity
- Identify the hazards of electricity. (6)
- Identify the effects on human body from electric shock. (6)
- Identify the factors that affect severity of electric shock. (8)
- Identify the possible reasons for accidents while using portable electrical equipment. (8)
5.2 Control Measures when working with using electrical equipment or electrical systems in all workplace conditions
- Outline ways to reduce the risk of receiving electric shock to workers using electric equipment. (8)
- Identify electrical hazards that could be identified by visual inspection. (8)
- Identify the emergency action to be taken in an electrical incident. (4)
- Outline the safety measures to protect against electrocution when:
(i) Excavating near underground cables
(ii) Working near overhead power lines
- Identify the advantages and limitations of:
a) Fuses (4)
b) RCDs (4)
- Outline how earthing can reduce risk of electric shock. (5)
- Outline the precautions that should be included in a safe system for work on a 230V electrical circuit. (8)
Some of the precautions that should be included in a safe system for work on a 230V electrical circuit are switching off electricity if possible and locking out the main switch to prevent re-energizing the system without the knowledge of the worker and testing the circuit to ensure that it is dead. Ensuring good lighting and sufficient space around the work area, segregating the work area by the provision of barriers, ensuring appropriate level of competence for workers. Providing suitable work equipment that are having insulated handles. Providing protective clothing and equipment for the workers such as fire proof clothing, face protection, insulating hand gloves, safety boots with insulating soles etc. Worker should avoid working in wet conditions and he should avoid wearing jewelry, watches etc. Precautions should be in place to deal with any emergency that might occur.
- Describe how the following two protective measures reduce the risk of electric shock AND, in EACH case, give an example of their application.
(a) Reduced low voltage.
(b) Double insulation.