In accordance with the basic elements constituting an accident, electrical accidents can be divided into five categories: electric shock accidents, electrostatic accidents, lightning disasters, radio frequency hazards, circuit failures and so on.
1, electric shock accident is caused by the energy of the current. Electrocution is an injury to the human body by electric current. The injury of electric current to the human body can be divided into electric shock and electric injury. The vast majority of electrocution injuries and deaths contain an element of electric shock.
2, electrostatic accidents refers to the production process and staff operation process, due to the relative movement of certain materials, contact and separation and other reasons and the accumulation of relatively static positive and negative charges. The electrostatic voltage may be as high as tens of thousands or even hundreds of thousands of volts, and may produce electrostatic sparks at the scene. In fire and explosion hazardous places, electrostatic sparks are a very dangerous factor.
3, lightning disaster is atmospheric electricity. Lightning discharge is characterized by high current and high voltage. Its energy release may produce great destructive force. Lightning may destroy facilities and equipment, but also may directly injure people, animals, may also cause fire and explosion.
4, radiofrequency radiation harm that electromagnetic field damage. The human body in the role of high-frequency electromagnetic fields absorb radiation energy, so that the central nervous system, cardiovascular system and other components will be subject to varying degrees of injury. Radiofrequency radiation hazard is also manifested as induction discharge.
5, circuit failure is caused by the transmission of electrical energy, distribution, conversion loss of control. Broken wire, short circuit, grounding, leakage, misclosing, misdrop, electrical equipment or electrical components are damaged circuit faults. Electrical circuit or electrical faults may affect personal safety.
Expanded:
One of the hazards
1, the human body's injuries
Electrical injuries caused by electric shocks and arcs, electrostatic injuries; electric shock is a certain amount of Current through the human body, causing bodily injury or dysfunction, or even death.
2, the object of the damage
Mainly caused by electrical accidents, fire, explosion, resulting in equipment and property destroyed. In the power transmission and equipment with a large number of flammable, combustible substances and high operating temperature, therefore, also has the risk of fire and explosion, once the accident, not only affect the safe operation of the power system, but also cause significant economic losses, serious environmental pollution and cause secondary accidents.
Two, prevent
1, the vast majority of cases, is the destruction of insulation is not found in time and when the elimination of defects in the equipment caused by personal electrocution and other electrical damage accidents, electrical professionals in the use of electrical equipment before the need for insulation testing.
Generally speaking, the megohmmeter determination, measurement of rated voltage 500 volts below the line or equipment insulation resistance, should be used 500 volts or 1000 volts megohmmeter (shaking table) should be based on the object to be tested to choose a different voltage level shaking table, shaking table 250 volts, 500 volts, 1000 volts, 2500 volts of four kinds.
Insulation resistance test can limit the leakage current of electrical equipment in a small range, which can play a role in preventing electric shock caused by leakage. Electrical equipment in the use of the necessary tests before the inspection, in order to detect problems in a timely manner to avoid accidents;
2, electrical equipment long-term overload and produce electrical short circuit, due to a short circuit caused by power supply interruption of power outage accidents. There are various reasons for short-circuit, but the main reason is that each line of each electrical equipment in use must be installed separately to protect the electrical appliances.
Reasonable configuration of a variety of corresponding protection appliances such as fuses, overcurrent disconnectors, thermal relays, thermal disconnectors, overcurrent relays, etc., the reasonable configuration of the protection of electrical equipment in the production of a variety of abnormal faults in the case of damage caused by an effective protection. Protection appliances can automatically cut off the power supply, the line and equipment to play a certain role in protection;
3, in the industrial enterprises, some of the more special environments and places, such as: flammable, explosive places, to understand their characteristics. In flammable and explosive and other places, electrical equipment in operation, the heat of the current and the current spark or arc, is the direct cause of accidents.
Prevention must have a comprehensive measures, including the selection of reasonable electrical equipment, to protect the necessary fire spacing, to maintain the normal operation of electrical equipment, keep well ventilated, to take the fire-resistant facilities, install good protective devices and other technical precautions.
Baidu Encyclopedia - Electrical Accidents