This article is devoted to understanding exactly what is meant by the term AWG fire alarm cable.

1. What Is AWG?
AWG stands for American Wire Gauge. The American Wire Gauge is a system designed to standardize measurements of electrical wire and cables. Designed in 1857 by Brown and Sharp, the system allows for easier calculations of current capacity and, therefore, significantly more streamlined implementation of wires.

AWG has been organized into reference tables based on the mathematics that built the standard. Using AWG reference tables allows even amateurs to determine safe and effective wire gauges for use in their projects.

2. What Do the Size Numbers Refer To?
Size numbers on cable listings refer to the thickness of the wire; the smaller the number, the thicker the cable. For example, a hypothetical 1 AWG fire alarm cable would be considerably thicker than 18 AWG fire alarm cable. Thicker cables offer a higher ampacity, which is a cable’s capacity for carrying electric current.

3. What Sets Fire Alarm Cable Apart From Other Cable?
The greatest difference between fire alarm cable and other types of cable is the type of insulation used. Because fire alarm cable is meant to connect systems which warn the occupants of a building that a fire could be present, alarm cable needs to be able to resist the heat at the beginning of a fire such that the system doesn’t become disconnected without alerting the occupants of the building.

Fire alarm cable actually has two very different designations, which determine the locations in which they are appropriate to use. Plenum-rated cable is fire alarm cable that is appropriate for use in spaces that have access to air circulation. Because air circulation can bring oxygen to fires in an emergency situation, plenum-rated cable needs to be more resistant to heat to account for the risk of stronger fires being present in their space.