AATCC 76:2005 pdf download.Electrical Surface Resistivity of Fabrics
1. Purpose and Scope
1.1 The purpose of this test method is to determine the electrical surface resis- tivity of fabrics. The surface electrical re-sistivity may influence the accumulation of electrostatic charge of a fabric (refer to AATCC Method 84 for determination of electrical resistance for yarns).
2. Principle
2.1 Specimens at equilibrium with specified atmospheric conditions of rela- tive humidity and temperature are mea- sured for electrical resistance between parallel electrodes by means of an electri- cal resistance meter.
3. Terminology
3.1 electrical resistivity, n.—material property of a substance whose numerical value is equal to the ratio of the voltage gradient to the current density. NOTE: For the purposes of this method, surface resistivity is calculated by using the measured electrical resistance be- tween superficially positioned parallel plates or concentric rings and their spac- ing and is reported as ohms per square. This test method in effect measures the resistance of a material to the flow of cur- rent between two electrodes.
4. Safety Precautions
NOTE: These safety precautions are for information purposes only. The pre- cautions are ancillary to the testing proce- dures and are not intended to be all inclu- sive. It is the user’s responsibility to use safe and proper techniques in handling materials in this test method. Manufac- turers MUST be consulted for specific details such as material safety data sheets and other manufacturer’s recommenda- tions. All OSHA standards and rules must also be consulted and followed.
6.1 Adjust the size of fabric test speci- mens to suit the electrodes of the particu- lar equipment being used. When using parallel plate electrodes, the width of the specimen must not exceed the width of the electrodes. When using the concentric rings, any size specimen at least as large as the outer ring may be used. Avoid con- taminating the area on which the mea- surement is to be made.
6.2 Specimens for use with instruments providing parallel plate electrodes. Pre- pare 2 sets of 3 test specimens each, 1 set each so that the direction of testing is par- allel to the yarns in the length direction of the fabric and 1 set with the direction of testing parallel to the width direction of the fabric.AATCC 76 pdf download.