ELECTRICAL SAFETY IN MANUFACTURING INDUSTRIES

Based On Experience , a number of rules and regulations have been framed for handling electrical appliances. If a person receives electric shock , mild or serious, directly or indirectly , the same must be reported as an electrical accident. In industry , an inquiry is normally ordered for every electrical accident. The following details shows the effect of electric current on human system.

Electric current and Effects :

1 to 8 ma - Perceptible but not painful.

8 to 15 ma - Painful shock ; Muscular control is not lost.

15 to 20 ma - Painful shock ; Muscular control is lost.

20 to 50 ma - Severe muscular contraction ; Breathing difficult.

50 To 100 ma - Ventricular Fibrillation ; a heart condition that results in instant death.

200 ma and above - Severe burns, clamp down the heart and stop it during the shock. This prevents the Ventricular Fibrillations.

All Items carrying electricity / having electric potential will have to be properly insulated. As the insulation have specific dielectric strength or voltage withstand capacity, the working voltage must, therefore , be kept substantially below the breakdown value. Ageing of insulation reduces the withstand capacity and should not be allowed to leak current. Switching contacts and points contacts should be checked periodically to avoid sparking and point heating.

The following preventive measures must be followed,

1. All metallic parts, externally accessible must be earthed.

2. Defective and worn-out fittings must be replaced promptly.

3. Inflammable materials should not be kept near electric appliances, live wires or electric control parts.

4. Safety devices like fuse, circuit breakers over-tripping switches must be used when required.

5. Untrained persons should not be allowed to repair electrical faults.

6. Safety belts, helmet, rubber gloves, boots with rubber soles and other safety items must be supplied to electric mechanics.

7. Standards of Safety items must be maintained as per norms.

8. Avoid Overloading any electric circuit.

9. Disconnect the electric appliances from main supply when not in use.

10. Avoid touching metal case of any electrical apparatus when it is in operation.

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