What is the function of fusible plugs in a chlorine cylinder?

Fusible plugs in chlorine cylinders serve a critical safety function by acting as a pressure relief mechanism in the event of a fire. These plugs are designed to melt at a specific temperature, which allows the contents of the cylinder to safely discharge if the temperature rises too high, preventing an explosive failure of the cylinder due to excessive pressure. This safety feature is crucial in protecting both personnel and the surrounding environment from the dangers associated with pressurized chlorine gas, which can be highly hazardous.

The other functions listed, such as regulating the flow of chlorine or maintaining temperature, do not accurately describe the purpose of fusible plugs. They are not used for indicating the cylinder's pressure either, as that would typically involve pressure gauges or other monitoring devices. The primary role of the fusible plug remains safety-oriented, specifically targeting the risks posed by high temperatures and preventing catastrophic failures.