SITE SAFETY

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SITE SAFETY

• HAZARDS AND PROCEDURES

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ELECTRICAL HAZARDS

• Electricity is a serious workplace hazard.
• Employees can be exposed to dangers such as
• Electric Shock
• Electrocution
• Burns
• Fires
• Explosion

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Electricity

• Some materials resist electricity better than
  others.
• For example Dry wood has a high resistance to
  electric current, but when wet it will readily
  conduct electricity.
• The same applies to human skin. When dry it has a
  fairly high resistance to electric current, but
  when moist, there is a radical drop in its
  resistance.

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ELECTRIC SHOCK

• Electric shock occurs when the body becomes part
  of the electric circuit.
• The current must enter the body at one point and
  leave at another.

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Electrical shock can occur in one of three ways

1. A person while in contact with the ground must
   come into contact with both wires of the
   electrical circuit.
2. A person can come into contact with one wire of
   an energised circuit and the ground.
3. A person can come into contact with a metallic
   part that has become hot by contacting with an
   energised conductor.

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BURNS

• A common shock related injury is a Burn.
• Electrical burns are a result of an electrical
  current flowing through bone and tissue.
• Electrical burns are one of the most serious
  injuries you can receive and should be given
  immediate attention.

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PREVENTION

• The metal parts of electric tools and machines
  may become energised if there is a break in the
  insulation of the tool or its wiring.
• People are made less vulnerable to electric shock
  with the use of earths.

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Earth wires

• People are made less vulnerable to electric shock
  with the use of earth wires.
• Earths use a low resistance wire that cause any
  unwanted current to pass directly to ground.
• This greatly reduces the amount of current
  passing through the persons body in contact with
  the tool or machine.

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PROTECTION

• Insulation will protect a person from
  electrically energised wires and parts.
• Insulators can be made from glass, rubber or
  plastic.
• Before using any tools check any cables for
  damage such as cuts.

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110 v

• All electrical equipment on British building
  sites is 110 volts.
• 110 volts is not enough to kill you.
• This therefore reduces the chance of fatalities.

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WORKING SAFELY

• All electrical equipment should be tested at
  regular intervals.
• PAT (Portable Appliance Testing) is carried out
  on all portable appliances used by employees, any
  public appliance in public places eg schools,
  hotels, any Hire Equipment and any repair or
  service outlets.
• PAT testing is required under HASWA.

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WORKING SAFELY

• Inspect before use that any leads or cords are
  intact and not damaged in any way.
• Check that the case or body of any tool is not
  cracked, damaged or loose in any way.
• Check triggers, switches or buttons work properly
  and do not stick or are loose.

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What to do

• Any Electrical Hazard should be reported to your
  Supervisor and isolated.
• Only use a DRY POWDER or CARBON DIOXIDE (C02)
  extinguisher on an electrical fire.

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FIRE SAFETY AND PROCEDURES

• THE FIRE TRIANGLE
• Fire requires three elements
• HEAT
• FUEL
• OXYGEN

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THE FIRE TRIANGLE

• A Fire can be prevented or extinguished by
  removing one of these elements.
• Without HEAT, a fire cannot begin.
• Without FUEL, a fire will stop.
• Without OXYGEN, a fire cannot begin, and it
  cannot continue.

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EXTINGUISHERS

• Different fire extinguishers are used to fight
  fires by acting on one of the three elements in
  the fire triangle.
• It is important to use the right fire
  extinguisher on the right type of fire.
• Fire extinguishers are colour coded according to
  their contents.
• Another type of fire extinguisher is a Fire
  Blanket.

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Extinguisher colours and use.

• WATER
• A water extinguisher is a red canister.
• Water works by taking the heat out of the burning
  material.

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WATER

• USE ON
• PAPER
• TEXTILES
• WOOD
• DO NOT USE ON
• ANY FLAMMABLE LIQUID.
• LIVE ELECTRICAL EQUIPMENT.

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DRY POWDER

• Dry powder is in a canister with a BLUE label.
• Works by making the flames too cool for the
  chemical reactions to continue.
• However, it does not cool the fire very well and
  care should be taken to make sure the fire does
  not flare up again.

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DRY POWDER

• USE ON
• PAPER,WOOD.
• FLAMMABLE LIQUIDS.
• LIVE ELECTRICAL
• GASEOUS FIRES

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FOAM

• Foam extinguishers are in a canister with a CREAM
  label.
• A foam extinguisher works by forming a blanket
  over the fuel of the fire.
• This prevents oxygen reaching the fuel.

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FOAM

• USE ON
• PAPER
• WOOD
• TEXTILES
• FLAMMABLE LIQUIDS
• DO NOT USE ON
• LIVE ELECTRICAL EQUIPMENT

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CO2 ( CARBON DIOXIDE)

• CO2 extinguishers are in a canister with a BLACK
  label.
• Works by removing the oxygen around the fire.
• Also removes the heat from the combustion zone

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CARBON DIOXIDE (CO2)

• USE ON
• FLAMMABLE LIQUIDS
• LIVE ELECTRICAL EQUIPMENT
• DO NOT USE
• IN A CONFINED SPACE
• CO2 does not work well on wood, paper fires. It
  may not displace enough oxygen to put the fire
  out, causing it to re ignite.

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KNOW YOUR EXTINGUISHERS

• USING THE WRONG TYPE OF
• FIRE EXTINGUISHER
• CAN BE LIFE THREATENING

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PROCEDURES

• Know where the fire assembly point is.
• Know where the fire extinguishers are.
• Make sure you dont block any fire escape routes
  with tools or equipment.
• If you discover a large fire, raise the alarm
  and leave the building immediately.