FACT SHEET

Working Safely with Electrical Equipment

Electricity is an essential part of our daily activities. While useful in powering electrical equipment, it can cause significant danger or harm if mishandled. Hence, it is important to understand basic electrical safety and the precautions to be taken by all staff working at or near electrical equipment.

Electricity is a serious workplace hazard which can lead to serious consequences such as severe injuries and death. Workers are exposed to electrical dangers during electrical installations or when operating machineries and power tools.

Types of electrical incidents include: Electric shock; Electrocution; Electrical burns; Loss of muscle control; Fire/explosions; and Damage to machineries.

Types of electrical hazards include: Defective equipment; Damaged electrical cords; Exposed wire; Overloaded circuits, plugs or extension cords; and Wet/damp conditions.

Case study 1

A worker received a fatal electric shock while attempting to operate an electric stirrer to mix some cement for plastering work at a construction worksite. Investigation revealed that a hand-twisted joint, taped with PVC insulation tape, was found on the power cord of the electric stirrer. Some loose strands of wires were found exposed at the joint. These strands of wires were live at the time of accident.

Case study 2

A worker received a fatal electric shock while carrying out arc welding work on a metal structure in a factory.

Investigation showed that: a. The welding electrode holder was not fully insulated. b. The insulation on the handle of the welding electrode holder was damaged. c. The voltage measured between the exposed metallic parts of the welding electrode holder and

the metal structure where the welding work was carried out was 70 volts. d. There was no low voltage shock preventor built in the welding set.

Results of studies from the International Electrotechnical Commission (IEC) Report Publication 479 showed that an adult person coming into contact with 70 volts a.c. would have a current of between 35mA (milli-ampere) and 70mA passing through his body, and he would be exposed to risk of ventricular fibrillation. The higher the current, the higher the risk.

Source: Energy Market Authority (http://elise.ema.gov.sg/elise/casestudy.jsp)

Reasonably practicable measures should be taken to protect any person against the risks of electric shock arising from the use of electrical equipment.

The following are some recommended safety measures when working with electrical equipment:

i) Ensure proper grounding of electrical equipment such that any electrical leakage current can flow from the equipment to the ground.

ii) Attend a prescribed refresher course once every 5 years for all licensed electrical workers.

iii) Check the electrical equipment voltage rating to ensure that it is suitable for connection to the electrical supply.

iv) Provide basic electrical safety training to workers who are exposed to electrical hazards.

v) Practice good housekeeping such as keeping the electrical equipment area dry and free of dust to maintain a safe work environment.

vi) Report hazards to supervisors immediately.

vii) Conduct visual inspections on electrical equipment before starting work daily.

viii) Use the Personal Protective Equipment (PPE) provided in the correct manner. Such items include insulating gloves, safety footwear and non-conducting clothing.

ix) Do NOT use: Cords or wires with damaged or worn insulation; Electrical equipment that smokes, sparks, shocks, smells, blows a fuse, or trips a

circuit; Cords or electrical equipment in areas with explosive or flammable materials that are

not approved specifically; Cords with a bent or missing grounding plug; Metal ladder when you are working near electricity; and Metal tools without proper insulation.

x) Do NOT touch: Any electrical equipment when your hands are wet, when you are standing on a wet

floor, or when you are in contact with a wet surface; and A victim of an electrical fire or an electrical shock.

xi) Do NOT place: Cords where they can be stepped on, run over by material handling equipment, or

damaged in any other way; Cords near heat or water; and Fasteners or nails on electrical cords.

xii) Do NOT permit: Overloaded outlets or circuits; Loose electrical connections; Dust or dirt buildup on machinery; Combustible trash on or around electrical equipment or circuits; Anyone who is not trained and qualified to repair electrical equipment; Attempts to use or start locked or tagged out electrical equipment; Unauthorised removal of a lockout device or tag; and Any hesitation in calling trained emergency responders for electrical fires, shock, or

serious burns.

Electrical equipment maintenance and repairs

i) Electrical equipment should always be included for safety audits or checks. Items to check for include defective parts, faulty insulation, improper grounding, and loose connections. Take appropriate corrective actions before working on or near live parts.

ii) Follow manufacturers instruction on cleaning and maintenance of electrical equipment.

ii) Workers performing maintenance and repair of electrical works should be Licensed Electrical Workers:

Have been fully trained to identify electrical hazards such as exposed electrical parts and the corresponding voltage.

Know the safety procedures to follow when they need to work on such exposed parts or in the vicinity of such hazards.

iii) Disconnect machine / electrical equipment The Lock Out / Tag Out (LOTO) System:

De-energize machines before doing any maintenance or repairs on them.

Ensure co-workers are at a safe distance at all times. Notify workers in the area that machine will be shutdown and locked out for

repairs / maintenance.

Turn off the machine.

Deactivate energy isolating devices the circuit breaker, disconnect switch, or other devices that provide energy to the machine.

Set lockout and/or tag out control switches to an "off" or "safe" position to prevent accidental start-up or energy release.

Release or block stored energy.

Test operating controls by pressing / turning the "on" position to ensure the machine does not start up. Then return operating controls to the "off" position.

Only authorised personnel should have the key for the LOTO device.

LOTO device should be removed only by the same authorised person.

If work is not completed before the next shift, lock should be applied by the next authorised shift worker before the departing personnel removes his/her lock.

Perform the necessary repairs or maintenance.

Remove tools and other items, and reinstall machine guards when work is completed.

Remove locks and tags, turn on energy and test to make sure machine is working properly.

Notify co-workers that the machine is ready for operations.

For more information, please refer to the following links:

1. Safety Daily Advisor. http://www.safetydailyadvisor.com

2. Energy Market Authority Electrical Safety. http://www.ema.gov.sg/Electricity/safety.php

3. Energy Market Authority. Electrical Case Studies & Lessons Learnt. http://elise.ema.gov.sg/elise/casestudy.jsp

4. Electricity Act (Cap. 89A)

5. Electricity (Electrical Workers) Regulations 2002.

6. Workplace Safety and Health Act

7. Workplace Safety and Health (General Provisions) Regulations.

8. Workplace Safety and Health (Construction) Regulations.

9. Singapore Standard CP 88: Part 1: 2001. Code of Practice for Temporary Electrical Installations. Part 1: Construction and Building Sites.

10. Singapore Standard CP 88: Part 2: 2001. Code of Practice for Temporary Electrical Installations. Part 2: Festive lighting, trade-fairs, mini-fairs and exhibition sites.

11. Singapore Standard CP 88: Part 3: 2004. Code of Practice for Temporary Electrical Installations. Part 3: Shipbuilding and ship-repairing yards.

12. Singapore Standard CP 5: 1998. Code of Practice for Electrical Installations.

13. Health and Safety Executive Electrical safety at work. http://www.hse.gov.uk/electricity/index.htm

14. MOM Circular to All Contractors on Electrical Safety. http://www.mom.gov.sg/publish/etc/medialib/mom_library/Workplace_Safety/bc_safety.Par.8227.File.tmp/Electrical%20Safety.pdf

15. NIOSH Safety and Health Topic: Electrical Safety http://www.cdc.gov/niosh/topics/electrical/

16. OSHA Health and Safety Topics: Electrical http://www.osha.gov/SLTC/electrical/index.html