Fire alarm cables are the cables that carry power and information to and from the nodes on a fire alarm system. When one alarm node sounds off, the system communicates that information with the other sensors on the network as well as with any control center that operates them. These systems are a critical component of the safety of manmade infrastructures and are regulated as a matter of law. That makes alarm wire and cable another matter that falls under this same umbrella of importance. Because an operable fire alarm system is so important to security as well as with legal compliance, it helps to understand the nature of the cables and wires that feed and service these systems. Here are some of the terms you are liable to come across in your search. Riser rated vs. plenum rated - Riser rated cables are rated for use in the vertical spaces between the floors of a building, and plenum rated cables are rated for use in plenum space - the space above a drop ceiling. Shielded vs. uns...