Specification for industrial duct heaters using metal-sheathed elements|Rated voltage, Electric wiring systems, Warm-air heating, Electrical insulation, Maintenance, Temperature, Electric heaters, Sheathed cables, Industrial, Electrical testing, Safety devices, Ducting, Installation, Electric cables, Electrical measurement, Testing conditions, Electrical connections, Thermal insulation, Air heaters, Clearance distances, Dimensions, Marking, Torque, Leakage paths, Rated power, Electric terminals, Heaters, Earthing, Fasteners, Electrical heating elements