Anti-static shoe standards for anti-static canvas shoes

National Standard for Electrostatic Shoes of the People's Republic of China and National Defense

.GB4385-1995 Technical Requirements for Anti-static Shoes and Conductive Shoes

.1 Power supply for test instruments Can output DC voltage 100V±2V. The measurement results can be accurate to within 5%, and the energy consumed on the test sample can be guaranteed to be no more than 3W.

The accuracy of the instrument's voltmeter and ammeter is 2.5, and the range can meet the measurement requirements.

A1.2 The internal electrode consists of a steel ball with a total weight of 4kg and a diameter of 5mm. And anti-oxidation treatment must be carried out before use.

A1.3 The external electrode is a copper plate. Anti-oxidation treatment must be carried out and cleaned with ethanol before use.

A2 Test Sample Preparation

A2.1 Sample Preparation

Clean the sole surface of the shoe to be tested with ethanol. Wash the soles with distilled water and dry them according to the conditions specified in A3.1. It is strictly prohibited to use organic substances for cleaning that will cause corrosion, swelling and deformation of the soles. The surface of the sole should not be abraded. Apply a conductive layer with an area of ??180mm × 40mm on the cleaned sole as shown in Figure A1, and place it to dry under the environmental conditions specified in A3.1.

A2.2.1 The device for measuring the resistance value of conductive coatings consists of three conductive metal pillars. The top radius of the metal pillars is 3mm±0.2mm. Two of the pillars are 35mm±0.2mm apart and connected with metal wires. The third pillar is 160mm±5mm away from the midpoint of the line connecting the other two pillars, and is insulated from the other two pillars.

A2.2.2 Place the shoes coated with the conductive layer on the metal pillars specified in A2.2.1. The forefoot part of the shoe is placed on two posts 35mm apart, and the heel part is placed on a third post. All three posts must be in contact with the conductive coating. Then use the test instrument specified in A1.1 to measure the resistance between the first two pillars and the third pillar. The measurement circuit principle is shown in Figure A2. As a result of the measurement, the resistance must be less than 1kΩ.

2. Introduction to relevant standards for anti-static safety shoes

European standard EN 344:1997 "Special Safety, Protective and Work Shoes". This European standard is composed of CEN/TC61 "Feet and Legs" "Protective Equipment" Technical Committee is formulated, and its secretariat is served by BSI. This standard stipulates the structure and performance indicators of safety protective shoes such as the style design, entire shoe, upper, lining, tongue, insole, and outsole. The test methods for each item specified in the standard are similar to other similar standards, and the method principles are also generally applicable to most safety anti-static protective shoes. The main indicators are:

1 Toe impact resistance

< p>Use a steel impact hammer with a specified weight to conduct an impact test. When the Baotou is impacted, the gap height under the Baotou should be less than the specified value, and the Baotou should not have any penetrating cracks in the direction of the test axis. It is worth noting that national standards have different regulations on the weight, specifications, impact height of impact hammers and the structure of the testing machine, which should be distinguished during actual testing.

2 Puncture resistance

The testing machine is equipped with a pressure plate, and the pressure plate is equipped with a test nail. The test nail is a head with the tip cut off. The hardness of the nail head should be greater than 60HRC. Place the sole sample on the chassis of the testing machine in a position such that the test nail can pierce through the outsole. The test nail pierces the sole at a speed of 10 mm/min ± 3 mm/min until it penetrates

Record the maximum force required until it penetrates. Select 4 points on each sole for testing (at least 1 point is at the heel). The distance between each point is not less than 30mm and the distance from the edge of the insole is greater than 10mm. There is a bottom with anti-slip blocks, which should be pierced between the blocks. Two of the four points should be tested within a distance of 10-15 mm from the edge line where the base corrugation is located. If humidity will affect the results, the soles should be immersed in deionized water at 20℃±2℃ for 16±1h before testing.

3 Electrical properties of conductive shoes and anti-static shoes

After the shoe samples are conditioned in dry and wet atmosphere, clean steel balls are filled into the shoes and placed on the metal On the probe device, use the specified resistance test instrument to measure the resistance between the first two probes and the third probe. Under normal circumstances, conductive shoes require a resistance not greater than 100K ohms; anti-static shoes require a resistance between 100K ohms and 100M ohms.

4 Requirements for anti-slip outsoles

This standard stipulates testing the anti-slip coefficient of anti-static work soles, but stipulates the design and specifications of anti-slip blocks, such as sole thickness, There are requirements for the height of the anti-slip block and the distance from the edge of the sole.

5 Anti-static shoes storage

5.1 Place

Should be stored in a dry and ventilated warehouse to prevent mildew. Stack them at least 0.2M away from the ground and walls. Stay 1M away from any heating element. Avoid contact with oil, acid, alkali or other corrosive substances.

5.2 Period

Products that are more than 18 months old from the date of production shall be inspected in accordance with the provisions of 5.2 of this standard and can only be sold and used if they meet the specified requirements.

6 Use of anti-static shoes

A. Wear anti-static shoes. When conductive shoes are not on the surface, wear thick insulating wool socks and insulating insoles.

The place where anti-static shoes are used should have an anti-static floor, and the place where conductive shoes are used should have a conductive floor.

B. During the wearing process, the resistance test should generally be performed once no more than 200H.