ANSI/ISA 60079-27-2006(12.02.04)
This standard contains the details of apparatus, systems and installation practice for use with the Fieldbus Intrinsically Safe Concept (FISCO) for installation and use in Class I, Zones 0 and 1 and the Fieldbus Non-Incendive Concept (FNICO) for installation and use in Class I, Zone 2. It is based on the concepts of Manchester encoded, bus powered systems designed in accordance with IEC 61158-2 which is the physical layer standard for Fieldbus installations..