The resistance of the conductive shoe was tested after being conditioned in both dry and humid environments to evaluate its electrical performance under different conditions.

Test Instrument
A DC voltage of (100 ± 2) V is applied during the test, allowing for a measurement accuracy of ±2.5%. This ensures reliable and consistent readings across multiple samples.

Internal Electrode
The internal electrode consists of stainless steel balls with a total weight of 4 kg and a diameter of 5 mm. To maintain conductivity, precautions must be taken to prevent or remove oxidation from both the steel balls and the copper plates. Oxidation can significantly affect the electrical properties of the materials.

External Electrode
The external electrode is made up of a copper contact plate that should be cleaned with ethanol before each use to ensure a clean and conductive surface.

Device for Measuring Conductive Coating Resistance
This device includes three conductive metal probes. Each probe has a radius of (3 ± 0.2) mm and is mounted on a base plate. Two of the probes are spaced (45 ± 2) mm apart and connected by a metal strip. The third probe is positioned (180 ± 5) mm away from the midpoint of the other two, and it is insulated from them to avoid interference.

Sample Preparation
If the shoe includes an activity mat, it should remain intact during testing. The sole should be cleaned with alcohol to remove any release agents, followed by a rinse with distilled water. After cleaning, the sample should be dried at (23 ± 2)°C. It is important not to rub or wear the sole, and no organic solvents should be used that might damage or swell the material.

Special Preparation for Wet Conditioning
For wet-conditioned samples, a conductive coating measuring 200 mm x 50 mm is applied to the sole, covering both the heel and forefoot areas. The dry resistance of this coating must be less than 1 x 10³ megohms. The shoe is then filled with clean steel balls and placed on the metal probes, with the forefoot area supported by two probes spaced 45 mm apart and the heel area supported by the third probe. The resistance between the third probe and the others is measured using the test instrument.

Based on the intended function of the tested shoe, the sample should be prepared according to one of the following conditions:

1) Dry Conditions: (20 ± 2)°C, relative humidity (30 ± 5)% – left to condition for 7 days.

2) Wet Conditions: (20 ± 2)°C, relative humidity (85 ± 5)% – left to condition for 7 days.

If testing cannot be conducted in a controlled environment, it must be completed within 5 minutes after the sample is removed from the conditioning chamber.

Test Procedure
Fill the shoe with 4 kg of clean steel balls. If necessary, use insulating material to raise the upper part of the shoe. Place the filled shoe on a copper plate and apply a (100 ± 2) V DC test voltage between the steel ball and the copper plate for 1 minute. Record the resulting resistance value.

During the test, the energy consumption of the sole should not exceed 3 W. If the voltage is reduced due to this power limit, the actual voltage used should be clearly noted in the test report.

China Labor Insurance Network