What is the difference between FS and FR cable?
The stark difference between flame-retardant and fire resistive cables is that the former resists the spread of fire into a new area, whereas the latter are designed to maintain circuit integrity and continue to work for a specific time even under a fire. Heat resistant – will operate as normal at high temperatures, but may not operate as normal in the event of a fire. Fire resistant – can operate as normal within fire conditions. Flame retardant – will not operate as normal within fire conditions, but will actively prevent the fire from spreading.