ELECTRICAL SAFETY W/ LOTO

Cards (56)

  • Electrical energy, like any other form of energy, can be completely safe when it is treated and handled with care by people who know the basic principles of its use
  • The abuse and misuse of electrical energy and its related components may result in serious injuries, fire, damage to plant and equipment, and even death
  • Every single part, material, and equipment is a potential source of electrical shock
  • Regardless of the shock's intensity, it can trigger an involuntary reaction that may result in physical harm
  • Electric accidents are classified as: a) electric shock caused by contact with charged or leaked parts of electric facilities b) a burn caused by discharge arc, c) eye injury caused by strong light from arc welding work; and d) fire or explosion ignited by overheat, sparks, leakage current, static charges, and the like
  • Related incidents and accidents can be avoided by implementing an efficient electrical safety policy and a hazard awareness and personnel training program
  • An efficient electrical inspection procedure must be held on a regular basis as circumstances permit
  • Voltage
    The difference in potential between points (measured in volts)
  • Current
    The movement or flow of electric charges (measured in amperes)
  • Resistance
    The property of a material that opposes the flow of electric current (measured in ohms)
  • Ohm's law
    The current flowing in a circuit is directly proportional to the voltage and inversely proportional to the resistance (V = IR)
  • Conductor
    Materials or substances that allow electricity to flow through them and have a very low resistance to electric current. Copper, Brass, Steel, Gold, and Aluminium are good conductors of electricity that are used in electric circuits and systems in the form of wires
  • Insulator
    A material that restricts the flow of heat, electricity, or sound, preventing energy transfer
  • Semiconductors
    Can change resistance to act as a conductor or insulator. Used to make computer microchips
  • Electrical Circuit
    A path for electrons created by connecting a conductor to a power source, with the current favoring the route of least/lowest resistance or lowest impedance
  • Circuit-Protection Devices (CPDs)
    • Fuses
    • Circuit Breakers
    • Ground Fault Circuit Interrupters (GFCIs)
  • Fuses
    Safety devices that operate to provide protection against excessive electric current. Its most critical component is a metal wire or strip that melts when exposed to excessive electricity
  • Circuit Breakers
    Electrical switches that protect an electrical circuit against damage caused by overcurrent, overload, or short circuit. Its primary role is to stop current flow once protective relays detect a problem
  • Ground Fault Circuit Interrupters (GFCIs)

    An extremely sensitive appliance, and a fast-acting power switch designed to shut off a circuit if there is a difference of more than 5 mill amperes between the hot and neutral wires or grounded conductors. It works by comparing the current going to and returning from the equipment along the circuit wires
  • Rules for Circuit Protection
    • Avoid octopus connections
    • Never bypass or disable circuit protection in an energized circuit
    • Ensure power is safely off
    • Replace a fuse with the exact duplicate
    • Use fuse pliers for added protection
    • Ensure old and new fuse markings match
  • Electrical shock
    The most serious electrical hazard
  • Electrical shock happens when a person touches a live wire, a tool, or a machine with poor insulation
  • 1mA at 60Hz is the minimum current at which a person feels an electric shock
  • 7mA to 8mA is the limit current at which a person can endure pain
  • 10mA to 15mA is the maximum current at which a person can still move
  • The heart is susceptible to electrical shock, which disturbs heart rhythm
  • Measures for Preventing Electric Shock Accidents
    • Maintenance and Inspection of Electric Facilities
    • Electric shock prevention when handling live lines and working near live lines
    • Electric shock prevention when handling power failure
  • Maintenance and Inspection of Electric Facilities
    • Inspect wiring, movable wires, switches, and all electric machines and equipment for complete insulation cover and enclosures. If any faults are identified, repair them immediately
    • Before using electric equipment, ensure that the earth conductor is connected, and undamaged, and verify that the earth pole is not floating
    • Before using welding machines, ensure the completeness of electrode holders, safety devices, and tools like automatic voltage-reducing devices for AC welding machines and leakage circuit-breaking equipment to prevent electric shocks
  • Electric shock prevention when handling live lines and working near live lines
    • When dealing with hotlines, installing insulation protectors and ensuring workers wear safety gear is essential
    • When working in proximity to high-voltage live lines, maintain a distance of within 30 cm overhead or 60 cm sideway or underneath live lines
    • Workers should wear insulation protective garments or safety devices must be in place, similar precautions are applied to low-voltage live lines
  • Safety Gear for Working with Live Lines
    • Electric Safety Helmet
    • Electric Rubber Gloves
    • Electric Insulation Garments
    • Electrical hazard (EH) rated safety boots
  • Electric Safety Helmet
    Designed for protection against accidental falls, protection from falling objects, and additional protection from overhead live wires while working on live lines
  • Electric Rubber Gloves
    Used to protect user's hand and forearms from electric shock and burns
  • Electric Insulation Garments
    Used to protect both shoulders and back from an electric shock
  • Electrical hazard (EH) rated safety boots
    EH boots have non-conductive soles to prevent electrical charges from passing through the body, ensuring the wearer is isolated from the ground
  • Electric shock prevention when handling power failure
    Ensure accurate recognition of hotlines and be cautious of residual electric charges as they can pose danger even after power failure. Use appropriate safety measures to mitigate this risk
  • First Aid Procedures
    • Mild Shock
    • Continuous Shock
  • Mild Shock
    • Sit, check muscle movement
    • Assess feeling, pulse, breathing
    • If no severe pain, resume work
  • Continuous Shock
    • Remove from power with non-conductive items
    • Assess airway, breathing, pulse
    • Get medical help after first aid
  • Lockout
    The process of blocking the flow of energy from the power source to the equipment. Lockout/tag out prevents machines from starting up unexpectedly or from releasing stored energy
  • Lockout-tag out procedure
    • Secure a disconnection switch, circuit breaker, or valve handle to prevent it from being moved while OFF or closed
    • A written tag should be attached where the equipment will be energized, such as an ON switch or a valve
    • Never block personal or unauthorized items with a LOTO
    • Never lend or borrow a lock
    • NEVER remove someone else's lock or tag