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Safety Management

The Risks of Electricity

Although electrical energy, convenient and pollution-free, is widely used in a variety of areas in our daily lives at home and school, when used incorrectly it is in the nature of electrical energy to cause disasters such as accidents or fires. Accidents and disasters caused by electricity can be categorized into several groups depending on the situation, but the main categories of accidents occurring in laboratories are electric shock and electrical fires.

Electric Shock

A sudden discharge of electricity through a part of the body due to an electrical appliance flowing with electricity can cause burns, disabling, or in worst case scenario, death.

The Impact of the Flow of Electric Current

Although the body cannot sense the flow of low-intensity electric currents, when the electric current grows in intensity, you can feel the intensity of the electric current based on the size X duration . This can become a serious threat causing pain, apnea, and suffocation.

Bodily Resistance to Electricity

Bodily resistance (impedance) determines the size of the flow of electric currents. This resistance is different depending on the authorized voltage. The worst-case scenario is approximately 1,000 ohms. It is important to set a high resistance value because the lower the value, the greater the danger.

The Impact of the Electric Current Route

The risk of electric shock to the body changes depending on the route of the electric current. When the electric current passes through the heart or the surrounding area, it influences the heart causing greater danger – cardiac electrical activity.

Electrical Fire

An electrical source causing a fire.

Form of the Causes of Fire

Electrical fires can be caused due to defects in the structure of electrical appliances, careless handling of electrical facilities, negligence, or not following safety regulations.

  • Cases of electric heaters/incandescent lights overheating and igniting surrounding combustible material.
  • Cases of wiring overheating and ignition of the wire covering.
  • Overheating of motors/transformers and other electrical appliances.
  • Short circuit/wire exposure/static electricity between wires.
Ignition Sources of Electrical Fires
  • Portable electric heaters such as electric cookers, electric irons, electric bedclothes, sterilizers, welders, etc.
  • Stationary electric heaters such as electric pyrostats, electric incubators, ovens, electric dehumidifiers, electric furnaces, and etc.
  • Electrical appliances such as distribution transformers, motors, generators, rectifiers, battery chargers, circuit breakers, and etc.
  • Wiring such as distribution wires, service wires, interior wires, cords, wire connections, and etc.
  • Wiring appliances such as switches, knife switches, automatic switches, cable splicers, multi outlets, electricity meters, and etc.
  • Wire exposures such as the connecting points of sheet zinc, connection point to walls, connection points of metal plates and pipes, wood in contact with with high-voltage lines, and etc.
  • Static electricity sparks caused by rubber film, rollers, liquid fuild in ducts, fission friction, and etc.
Sources of Electrical Fire
Sources of Electrical Fire
Short Circuit (circuit interruption) In certain cases where short-circuiting is caused, due to the stripping of the wire covering or nailing/pinning of the wire, a spark occurs with an instant explosive sound and the short circuit point fuses. When this occurs, a fire can start if there is combustible material in the surroundings or the wire itself can ignite due to overheating.
Short Circuit and Ground Fault If the wire covering or the insulation of the electrical appliance is overheated or damaged, the electric current passes through the conductor and leaks onto the ground. This phenomenom is known as ground faulting and causes ground fault fires by igniting surrounding flammable material.
Overcurrent When an electric current flows through a wire, heat in proportion to double the electric current and double (I2XR) the resistance value of the wire occurs. If an electric current surpassing the allowed current flows continuously, the wire overheats and causes the wire covering to ignite. This occurs more frequently with PVC insulated wires.
Electric Spark Sparks occur when an electric circuit is made or broken or a fuse melts and occurs especially when a circuit is cut. If there is volatile steam or combustible dust present, they will ignite/inflame.
Insulation Deterioration and Charring Most wiring insulation is made of organic matter. Generally, when the organic matter stiffens over an extended period of time, the insulation resistance rate declines. In areas with poor air ventilation and high temperatures, overheating leads to the charring process taking on conductivity. If a voltage passes through this point, the charring process is progressively sped up because of the electric current. When this occurs the organic material iteself will burn or the combustible material in the area will ignite.
Electrical Overheating When an electric current flows through an incomplete connection between wires or sockets, overheating caused at the connection resistance area ignites the surrounding insulating material.
Static Electric Spark Depending on the intensity of the material friction causing static electricity, the spark occurring from the charge up can ignite combustible material in the surrounding area.
KAIST, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea / T. 042-350-2114 / F. 042-350-2210 (2220)

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