Electrical performance protective footwear knowledge
The electrical properties of protective footwear and personal protective equipment, protective shoes for foot protection, including anti-static footwear and conductive and dielectric footwear, to prevent electrostatic damage and electrical shock.
The dangers of static electricity on the human body
Electrostatic damage to the human body: cause psychological barrier, resulting in fears, in order to cause the accident, also cause skin burns, and dermatitis due to electrostatic shock. Static hazards, flammable and explosive accidents occurred in the industry, thereby endangering the lives of workers and cause significant loss of production facilities.
An electrical shock is a common work-related injuries can be divided into contact with electrical injury and non-contact electrical injury. The former is mainly the current injury, it can damage the body's internal tissues, such as heart, respiratory system, nervous system. The light pins and needles, to combat a sense, there trembling, cramps, high blood pressure, irregular heart beats, until he lost consciousness; severe cases, ventricular fibrillation, cardiac arrest, respiratory arrest and even death. The latter arc hurt the performance of the mark for electrical, electrical burns, skin carbonation, severe cases can be deep and muscles, bones and internal organs.
The study of human physiological showed that an electric shock, the current of human perception, the average adult male 1.1 mA, the average adult female is 0.7mA; out of current, the average adult male is 16mA, the average adult female is 10.5mA. When the electric shock current is greater than to get rid of the current, electric shock and can not take the initiative to get rid of power, such as no outside help, it will extend the time of electric shock, the risk of death occurs. Hands, feet, parts of the current through the body most prone to injury.
Classification of the electrical properties of protective footwear
The anti-static shoes and conductive shoes may be material into the shoes and cloth shoes and shoe production process can be divided into adhesive class, injection and molded-class. Electrical insulation of shoes according to the material is divided into leather shoes, rubber shoes cloth, plastic surface of rubber shoes and plastic shoes. Shoes adhesive production process can be divided into classes, molded category, injectable line sewing class. The anti-static shoes can eliminate the accumulation of body static, but also to prevent the 250V power electric shock protective footwear. Conductive shoes have good conductive properties, the body accumulation of static electricity in the short and can only be used for protective footwear risk of electric shock places. Dielectric footwear can make a person's feet and charged objects insulation, prevention of electric shock injury protective footwear.
The technical requirements of the electrical properties of protective footwear
Anti-static shoes and conductive footwear according to GB4385-1995 "anti-static shoes, conductive shoes technical requirements under the resistance value range of 100k ~ 1000M and not more than 100k. Among them, the shoes should be consistent with the provisions of GB1002-1005; cloth sneakers should the HG/T2495 provisions. The main technical characteristics of the anti-static shoes and conductive shoes in addition to electrical properties, outsole wear volume, around the bar and upper adhesion strength, folding outsole, outsole wear into shoes, peel strength, and other standards.
Dielectric footwear should conform to the provisions of the GB12011-2000 "General technical requirements for dielectric footwear". Electrical insulating shoes and electrical insulation of the electrical properties of the cloth shoes, should meet the requirements of Table 1: When the leakage current 0.3mA/kV.
Electrical insulating rubber boots and electrical insulation of the electrical properties of polymeric materials boots as follows: When the leakage current 0.4mA/kV, should meet the requirements of Table 2.
The main technical performance of the insulated shoes in addition to electrical properties, as well as upper and confining the adhesion strength, upper tensile properties of the upper fabric adhesion strength, folding outsole, outsole wear into shoes, peel strength and permeability water-based and so on.
Electrical properties of the choice of protective footwear
With electrical properties of protective footwear should be in accordance with the national standard GB11651-1989 "labor protective equipment selection rules and the State Economic and Trade Commission on March 6, 2000 release of" labor protective equipment with standard (Trial) "or place the relevant provisions of the industry execution protective type of injury and the working environment, but also carry out selected risk factors such as the work environment is mainly electrostatic damage, and the work of the ground conductive ground, considering the selection of conductive shoes; may also have low voltage (250V) electric strike hazards in the workplace, and the work of the ground for the anti-static ground, considering the selection of anti-static shoes. The anti-static shoes and conductive footwear is mainly used in petrochemical, pharmaceutical and electronics industries. If the major risk factors in the work environment is an electric shock injury, dielectric footwear should be used in live working.
In addition, the user work environment, the choice of protective footwear of the electrical properties of different materials. Such as most of the electronics industry and the pharmaceutical industry, the environment clean, the work of relatively low intensity (move around less), can be used on canvas rubber-soled anti-static shoes or conductive shoes, lightweight and comfortable, breathable better. The petrochemical industry, including fuel (gas) stations, the working environment more complex, work intensity is relatively high (to move around more), use anti-static shoes or conductive shoes, and more dirt, wear. Similarly, the power frequency voltages from 1kV charged workplace and the environment is drier, the choice of resistance, voltage below 15kV electrical insulating shoes or electrical insulation on canvas rubber shoes. In the power frequency voltage above 1kV, workplace, or more humid environment, the choice of resistance over voltage 15kV electrical insulating rubber boots or electrical insulating plastic boots. When used, must also strictly comply with the provisions of the electrical safe work procedures (DL408 and DL409).
Shoes class electrical properties of protective footwear can also be based on the user's preferences, the choice of different production processes and the appearance of quality products. At present, the more common of adhesive and injection shoes, seam class shoes and more tires the bottom and anti-wool insulation shoes, molded shoes is now rarely used. Appearance quality is generally more easy to judge, such as the uppers disability, different color and line weight needle, the needle jump, break the pin code uneven, to help the end of the open plastic, off-line, soles and rubber surface over sulfur, less sulfur, spraying sulfur. The intrinsic quality you need to inspect the product factory inspection certificate, inspection of the inspection reports issued by the third-party inspection agency approved by the national government departments as the basis to judge the quality of products the pros and cons.
Sign of the electrical properties of protective shoes
Antistatic shoes, conductive shoes and dielectric footwear belong to a special labor protection articles. National implementation of the special labor protection supplies safety signs management and production permit system. The manufacturers of these products must obtain a special labor protection products safety signs management center, signs the certificate issued by the safety and industrial products production license only after the production and sales in the certificate is valid. In addition, manufacturers must also be printed on the product and packaging meet the standard requirements of signs, along with product specifications and certification, as well as the safety mark and QS logo.
The end of the outside of antistatic shoes, conductive shoes, inner soles or uppers should have the following signs: soles anti-static / conductive "words;" GB4385 "standard code; inspection seal; trademark; shoes shoe. Product packaging should be standard code name site, product name, logo,
Shoe shoe, trademarks, the use of notes, the date of manufacture and production lot. Dielectric footwear (boots) should have the following flags: should be standard number on the uppers or soles of every pair of shoes, electrical insulation, the words (or English, EH), lightning mark and withstanding voltage value; manufacturer's name, shoe, product or trade name, production month, day, and electrical insulation factory inspection seal. The product packaging should be the standard number, manufacturer name, product name (eg: the 6kV cow leather surface insulated shoes), shoe, trademarks, Use.
Enterprises in the purchase of these products should require dealers to produce a batch of product test reports, and the manufacturer of the product safety signs the certificate and production license copy, and archive the record.
Electrical properties wear protective shoes
Wear antistatic shoes, conductive shoes should not wear insulated woolen thick socks or insoles padded insulation. Sites should use anti-static shoes, anti-static ground, the place of use of conductive shoes should be conductive ground. Wear process is generally not more than 200h resistance test should be carried out 1. Should be stored in dry and ventilated place, avoid contact with oil, acids, alkalis or other corrosive substance. Calculated from date of manufacture, inspection and electrical properties of the product should be more than 18 standard specifies, in line with the requirements before sale and use.
Wear shoes and electrical insulation cloth shoes, electricity insulation, the working environment should be able to keep the upper dry. Wear any shoes, electrical insulation should avoid contact with sharp, high temperatures and corrosive substances, to prevent shoe damage affect the electrical properties. Help the end of corrosion, damage place, can no longer be used as the dielectric footwear. Calculated from date of manufacture, the products have to be over 24 months by only the preventive inspection of the electrical properties, dielectric footwear sales and use meet the requirements side. Each preventive test results for a period not more than six months.| Updated:2012.02.03 Source: Clicks:1639
