Electrical protective shoes are protective shoes used t […]
Electrical protective shoes are protective shoes used to protect the feet in personal protective equipment, including anti-static shoes, conductive shoes and electrical insulating shoes, which can prevent electrostatic injury and electric shock injury.
The harm of static electricity to the human body
The damage caused by static electricity to the human body includes: causing psychological barriers, generating fear, and causing accidents, and can also cause skin burns and dermatitis due to electrostatic shock. The main hazard of static electricity is that flammable and explosive accidents occur in the industry, which endanger the lives of operators and cause heavy losses to production facilities.
Electric shock injury is a common industrial accident, which can be divided into contact electric injury and non-contact electric injury. The former is mainly electrical damage, which can damage the internal tissues of the human body, such as the heart, respiratory system, and nervous system. Mild cases may experience acupuncture, a sense of blow, tremors, spasms, increased blood pressure, arrhythmia until coma; severe cases may cause ventricular fibrillation, cardiac arrest, respiratory arrest and even death. The latter is mainly arc injury, manifested as electric branding, electric burns, skin carbonization, and in severe cases, it can penetrate deep into muscles, bones and internal organs.
The study of human electroshock physiology shows that the perceptual current of human beings is 1.1mA on average for adult males and 0.7mA for adult females. When the electric shock current is greater than the escape current, the electric shock person cannot actively get rid of the power source. If there is no external help, the electric shock time will be prolonged and the danger of death will occur. The hands and feet are the most vulnerable parts of the human body when electric current passes through them.
Classification of electrical protective shoes
Anti-static shoes and conductive shoes can be divided into leather shoes and cloth rubber-soled shoes according to the material, and leather shoes can be divided into adhesive, injection and molding according to the production process. Electrically insulating shoes can be divided into leather shoes, cloth rubber shoes, rubber rubber shoes and plastic shoes according to the material. Leather shoes can be divided into adhesive, molding, injection and seam according to the production process. Anti-static shoes are protective shoes that can not only eliminate the accumulation of static electricity in the human body, but also prevent electric shocks from power sources below 250V. Conductive shoes are protective shoes with good electrical conductivity, which can eliminate the accumulation of static electricity in the human body in a short time, and can only be used in places where there is no danger of electric shock. Electrically insulating shoes are protective shoes that can insulate people's feet from charged objects and prevent electric shock injuries.
Technical requirements for electrical protective footwear
Anti-static shoes and conductive shoes are stipulated in GB4385-1995 "Technical Requirements for Anti-static Shoes and Conductive Shoes". Among them, leather shoes should comply with GB1002-1005 regulations; cloth rubber-soled shoes should comply with HG/T2495 regulations. In addition to the electrical performance, the main technical performance of anti-static shoes and conductive shoes also include the wear amount of the outsole, the adhesion strength of the fence and the upper, the folding resistance of the outsole, the wear resistance of the outsole, and the peeling strength of the finished shoe.
Electrically insulating shoes shall comply with the provisions of GB12011-2000 "General Technical Conditions for Electrically Insulating Shoes". The electrical properties of electrically insulating leather shoes and electrically insulating cloth shoes are: when the leakage current is 0.3mA/kV, the requirements in Table 1 shall be met.
The electrical properties of the electrically insulating rubber boots and electrically insulating polymer material boots are: when the leakage current is 0.4mA/kV, they shall meet the requirements of Table 2.
In addition to electrical properties, the main technical properties of electrically insulating shoes include the adhesion strength between the upper and the strip, the tensile properties of the upper, the adhesion strength between the upper and the fabric, the folding resistance of the outsole, the wear resistance of the outsole, the peeling strength of the shoe, and the water seepage. sex, etc.
The choice of electrical performance protective shoes
The equipment of electrical performance protective shoes should be in accordance with the national standard GB11651-1989 "Labor Protection Equipment Selection Rules" and the "Labor Protection Equipment Equipment Standard (Trial)" issued by the State Economic and Trade Commission on March 6, 2000 or relevant local and industry regulations. The implementation can also be selected according to the type of injury protection and the working environment. For example, if the dangerous factor in the working environment is mainly static electricity damage, and the working ground is conductive ground, you can consider using conductive shoes; and there may be low-voltage (below 250V) electric shocks at the same time. Hazardous workplaces, and the work floor is anti-static ground, you can consider using anti-static shoes. Anti-static shoes and conductive shoes are mainly used in petrochemical, pharmaceutical and electronic industries. If the main risk factor in the working environment is electric shock injury, electrical insulating shoes should be used when working with electricity. In addition, users can choose electrical protective shoes of different materials according to the working environment. For example, in most electronic industries and pharmaceutical industries, the environment is relatively clean and the work intensity is relatively low (less walking). Cloth rubber-soled anti-static shoes or conductive shoes can be selected, which are light, comfortable and breathable. In the petrochemical industry, including refueling (gas) stations, the working environment is more complex and the work intensity is relatively high (more walking). Anti-static leather shoes or conductive leather shoes can be used, which are more resistant to dirt and wear. Similarly, in the live work place where the power frequency voltage is below 1kV, and the environment is relatively dry, electrical insulating leather shoes or electrical insulating cloth rubber shoes with a withstand voltage below 15kV can be selected. In the workplace where the power frequency voltage is above 1kV, or the environment is relatively humid, electrical insulating rubber boots or electrical insulating plastic boots with a withstand voltage of more than 15kV can be selected. When using, must also strictly abide by the electrical safety work regulations (DL408 and DL409) regulations.
Leather shoes electrical performance protective shoes can also be selected according to the user's preferences, products with different production processes and appearance quality. At present, glued and injected leather shoes are more common, stitched leather shoes are mostly car tire soles and suede insulated leather shoes, and molded leather shoes are rarely used now. Appearance quality is generally easier to judge, such as whether the help surface is disabled, the color is different, the stitches are doubled, the stitches are skipped, the thread is broken, and the stitch size is uneven.