BIS
IS 5571
Guide for Selection of Electrical Equipment for Hazardous Areas
The Indian guide for selecting equipment by zone, gas group and temperature class, used alongside IS/IEC 60079 and IS 5572 for area classification. It matters because Indian statutory approval runs through this route rather than through ATEX, so an imported certified device still has to be shown acceptable in these terms, and because it is the document a statutory inspector is most likely to open when questioning an installation.
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