4.4 Measurement conditionsThe test load applied during the measurement is (80 t 5) % of the maximum tyre load capacity marked; single load if both single and dual load are marked. The inflation pressure is equal to (80+5) % of the pressure corresponding to the maximum tyre load. The inflation pressure to be registered in the test report shall be appropriate for the test load applied. Ambient temperature during the measurement shall be maintained at (25+5-10)℃. Relative humidity shall be lower than or equal to 60 % during the measurement procedure.The approved wheel (preferably steel) shall be stripped clean in the bead seat area, as well as at the connecting point. It is necessary to make sure the tyre is dry before taking the measurement. Dry mount the tyre if possible. To avoid damage to tyre in the case of difficult mounting conditions, a water-soluble mounting solution can be used. Any mounting solution on the sidewall or tread of the tyre shall be cleaned and dried. Mark a reference point on the tyre sidewall with ล non-conductive material. Set up the apparatus as shown in Figure 1. Clean the metal loading plate with isopropyl alcohol or a similar agent and allow to dry. Conductive or non-conductive substances on the tyre which could affect the result, such as mould release agents, paints or both, shall be removed. The use of organic solvent, which is likely to attack the rubber, is prohibited. Connect the ohmmeter leads to the metal loading plate and the wheel.Load the tyre-wheel assembly at the reference point to the value as specfied in 4.4, hold for 1 m,and then remove the load. Repeat the load- unload cycle a second time. If the resistance is less than 1010 Ω, the current should be not less than 10-7 A and the voltage no than 1000 V (see Table 1). Load the tyre a third time to the test load and immediately apply the test immediately apply the test voltage. Record the resistance measurement 3 min±10s after the voltage has been applied.The voltage and the load shall be applied continuously to the tyre until the final measurement 1s recorded. Unload the tyre. Repeat the preload cycle and measurement for at least two other additional circumferential locations approximately evenly spaced around the tyre..