Suzhou Electrician Training [http://www.bangyuanedu.com/wzny.asp?id=1037] - With the continuous progress of society, electric energy has become the most basic and irreplaceable energy source in people's production and life. However, when electric energy gets out of control, it can trigger various electrical accidents, among which electric shock accidents are the most common type of accident involving harm to the human body.
As we all know, electric shock accidents are caused by current [http://www.bangyuanedu.com] in the form of energy. There are many differences in their forms and ways of causing harm. Overall, they can be divided into two types of electric shock accidents and three types of electric shock.
1. Types of Electric Shock Accidents
According to the way electric shock accidents occur, they can be divided into electric shock and electric injury.
1. Electric Shock
Electric shock is the damage caused by current to the internal tissues of the human body, which is the most dangerous kind of injury. The vast majority (more than 85%) of electric shock fatalities are caused by electric shock. The main characteristics of electric shock include:
(1) Damages the inside of the human body
(2) No significant marks on the surface of the body
(3) A smaller fatal current
Based on the state of the electrical equipment during an electric shock, electric shock can be further divided into direct contact electric shock and indirect contact electric shock.
(1) Direct Contact Electric Shock: This occurs when a person touches live parts of equipment or wiring during normal operation (such as accidentally touching a live terminal). It is also called an electric shock under normal conditions.
(2) Indirect Contact Electric Shock: This happens when a person touches parts that are not normally live but become live due to equipment or wiring faults (such as touching the casing of a leaking device). It is also referred to as an electric shock under fault conditions.
2. Electric Injury
Electric injury refers to harm caused by the thermal effect, chemical effect, and mechanical effect of current on humans. In electric shock casualties, purely electric injuries and those with electric injury components account for about 75% (electric burns account for approximately 40%). Although over 85% of electric shock fatalities are caused by electric shock, around 70% contain elements of electric injury. For the safety of professional electricians themselves, preventing electric injury holds even greater significance.
(1) Electric Burns: These are injuries caused by the thermal effect of current, categorized into current burns and arc burns.
Current burns occur when the human body comes into contact with live parts, and the current converts electrical energy into heat, causing injury. Current burns typically happen in low-voltage devices or low-voltage circuits.
Arc burns are injuries caused by arc discharges, divided into direct arc burns and indirect arc burns. Direct arc burns occur when an arc forms between live parts and the human body, with current passing through the body, causing burns; indirect arc burns happen when arcs near the human body cause burns, including scalds from splashes of molten hot metal. Direct arc burns occur simultaneously with electric shocks.
Arc temperatures can reach above 8000°C, causing extensive and deep burns, potentially burning or charring limbs and other parts. High currents passing through the human body may also dry out and char body tissues. Burns from high-voltage arcs are more severe than those from low-voltage arcs, and DC arc burns are more serious than industrial frequency AC current burns.
(2) Metalization of Skin: This occurs when metals melt and vaporize under the high temperature of an electric arc, and metal particles penetrate the skin, making it rough and taut. Skin metalization often occurs simultaneously with arc burns.
(3) Electric Branding: This leaves permanent scars at the points where the human body contacts live parts. The scarred areas lose their original elasticity and color, with the epidermis dying and losing sensation.
(4) Mechanical Injury: This results from the effects of central nervous system reflexes and strong muscle contractions when current acts on the human body, leading to tissue tears and fractures.
(5) Electric Light Eye: This involves eye injuries caused by infrared, visible light, and ultraviolet rays during arc discharges. Electric light eye manifests as keratitis or conjunctivitis.
Stay tuned for the next issue of Suzhou Electrician Training [http://www.bangyuanedu.com/wzny.asp?id=1037] regarding electric shock methods [http://www.bangyuanedu.com].
Related articles: 2012 Accounting Qualification Examination Training ~ Suzhou Accounting Certificate Training ~ Suzhou Accounting Training Class ~ Suzhou Accounting Practical Operation Class 2012 Basic Accounting Review - Suzhou Accounting Training - Suzhou Accounting Window "Thief Strike - Your home is too poor!"