VCAL WORK RELATED SKILLS - SENIOR - Unit 1
Infosheet 6. Electricity Electric shock happens when a person becomes part of an electrical circuit and the current flows through their body. When an electric shock kills someone it is called electrocution.
Accidents and deaths can occur when equipment becomes 'live' due to electrical faults, lack of maintenance, or short circuits. Doing maintenance work on live electrical circuits is another common cause of electrocution.
Electrical accidents are usually caused by a combination of factors such as: •
lack of training or supervision
•
unsafe work practices
•
equipment not properly installed, maintained, tested and tagged
•
a hazardous work environment, where electrical hazards may not be recognised.
Electrocution often occurs when people misjudge heights and distances between the ground and overhead wires when carrying equipment like poles and ladders, or operating equipment with height extension such as cranes. Remember, 'Look Up and Live'.
General safety precautions •
Apprentices, trainees and work experience students must be supervised at all times by a qualified worker,
and must never attempt to carry out any work that could expose them to an electrical hazard. •
Only licensed electrical workers can legally do electrical work. An unqualified person must not be asked to
do electrical work. •
Keep powered tools and equipment in safe working order through inspection and preventative maintenance
programs. •
Disconnect and report faulty tools and appliances - for example, frayed cords or broken power points. Even
after a piece of electrical equipment, appliance or machine has been disconnected from the power source, it may
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VCAL WORK RELATED SKILLS - SENIOR - Unit 1
still partially operate. This is because of stored energy within the equipment. After disconnecting the power source, activate the machine or appliance to release the stored energy. •
Always switch off tools and appliances at the power point before pulling out the plug.
•
Keep electrical cords off the floor to reduce the risk of damage from dragging, contact with sharp objects or
contact with water. A damaged electrical cord can cause electrocution. •
Know the location of your main electricity supply.
•
Check the location of overhead wires and stand clear of any fallen power lines.
•
Use your appliance properly. Read the instruction booklet and follow all instructions.
•
Electricity and water don't mix. Bare feet and wet skin lower the body's resistance to electricity. Keep
electrical appliances and electrical leads away from water and wet areas. •
Don't overload circuits and fuses by using too many appliances from the one power point. Don't use double
adaptors to 'piggy back' plugs. Use a power board with individual switches. •
Employees who use portable electrical equipment at workplaces must be protected against earth leakage
by a Residual Current Device (RCD), also known as a safety switch.
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VCAL WORK RELATED SKILLS - SENIOR - Unit 1
Worksheet Sentence Match TASK: Using the ‘Infosheet’ above pair the sentence fragments.
1. A “dead man” switch …
… a qualified electrical worker at all times.
2. Working safely with electrically powered tools and
… is designed to immediately switch off the current when
equipment requires safe working procedures and
electricity leaking to earth is detected at a level harmful to
training, …
a person using electrical equipment.
3. Electrical work should legally only be carried out by … 4. A residual current device …
… electrical arcing and flying objects. … bracelets, rings, neck chains, exposed metal zips or watches.
5. Apprentices and trainees must be supervised by …
appropriate tools and the right protective clothing.
6. Safety glasses provide protection from …
… the level of voltage they are able to insulate against.
7. Rated insulated gloves are designed for live work
… fix appropriate tags, test that the electricity supply is
and are rated according to … 8. Safety helmets provide protection from … 9. While carrying out electrical work near live electrical equipment you should not wear … 10. Before you start electrical work, you should switch off, isolate circuits, …
isolated and test your instruments. … a licensed electrical worker. … is designed to switch off current so a machine stops when the operator releases pressure on the switch, handle or pedal. … over-head wires, structures and falling objects.
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VCAL WORK RELATED SKILLS - SENIOR - Unit 1 Â
Missing Words Complete the Missing Words exercise below.
1. A ___________________ tag on an item of equipment or machinery is a ___________________ to all persons that the equipment or machinery is being worked on and ___________________ ___________________ be ___________________ as lives may be placed in danger.
2.
When _____________ or ______________ people are working on the same job they must each fix their own ________________ ___________.
3.
A circuit must not be __________________ while a __________________ tag is attached.
4.
__________________ and black ________________ __ _________________ tags are used to warn people that machinery,
appliances
or
equipment
are
___________________
,
___________________
or
_________________ ___ _________________ for repairs, maintenance or inspection. These tags are used to prevent _________________ and damage to the ___________________ or ___________________.
Scrambled Words Unscramble the following words below.
KCGINOL TOU
__________________________________________________
PMTENIUQE
__________________________________________________
IUDEARSL
__________________________________________________
CCEETRYLTII
___________________________________________________
URCRTEN
___________________________________________________
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VCAL WORK RELATED SKILLS - SENIOR - Unit 1 Â
Short Answer Exercise Complete the Short Answer exercise on locking out and tagging equipment.
1. What is the reason for using isolation, tagging and lock out procedures?
2.
What is the best way of preventing machinery or electrical current from becoming operational during maintenance?
3.
Name the two main types of tags and briefly explain the use of each.
4.
What colours are the two tags?
5.
State who is allowed to remove each type of tag and why.
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