If a Category 3 groundable garment is tested using a resistance meter in conjunction with the operator (TR53 7.2.2.1.2 Resistance Measurement Apparatus), and the measured resistance falls within the acceptable limits, is it still required to perform an individual resistance test from the end of one sleeve to the garment’s designated ground connection point (TR53 7.3.17.1 Resistance to Groundable Point
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Alex,
ANSI/ESD S20.20 requires in section 8.2 “When garments are used to achieve personnel grounding, it shall be documented in the ESD control program plan. It shall also meet the groundable static control garment system resistance requirements defined in Table 2 and the groundable static control garment in Table 3.” For compliance verification, the requirements for a groundable static control garment system are system resistance less than 3.5 x 10^7 ohms and the groundable static control garment requires point to groundable point of less than 10^9 ohms. The measurement for the groundable static control garment system includes the person through the cuff and then through the garment to the groundable point either through the garment fabric or a separate wire and then through the test equipment. The groundable static control garment measures the resistance from the cuff and then through the garment to the groundable point either through the garment fabric or a separate wire. The only difference is the person’s resistance is not in the groundable static control garment. Currently the product qualification requirements have a test for the garment panels themselves, but the compliance verification requirements do not. I asked John Kinnear, the working group chair for S20.20, about this and he sees that we need a compliance verification test for the panels and will talk to the working group chair of TR53 about it.
But to answer your question, technically, yes, if you meet the compliance verification requirements for the groundable static control garment system you should also meet the requirements for the groundable static control garment. Still, it is probably best to do a panel point to groundable point compliance verification to ensure the garment is conductive which shows you that your garment panels are working as expected.
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Thanks Andy,
You really do learn something new every day! I hadn’t used the grounding through the garment before, so I totally missed that last part in section 8.2. Thanks a lot for clearing it up!