Which safety device is designed to prevent excessive pressure buildup in the boiler?

The pressure relief valve is specifically designed to prevent excessive pressure buildup in a boiler. This device functions as a critical safety mechanism, allowing steam or water to escape from the boiler when pressure reaches a predetermined safe limit. If the pressure exceeds this threshold, the valve opens, enabling the release of excess pressure and thereby preventing potential hazards such as boiler rupture or explosion. This function is vital to maintaining safe operational conditions within the boiler system.

In systems that involve pressurized fluids, having this safety device is essential for protecting both the equipment and the personnel involved. Other options such as a temperature gauge, control actuator, and flow switch serve different purposes; they monitor conditions or assist in controlling the system rather than directly managing pressure levels. Therefore, the pressure relief valve stands out as the key component for pressure safety in boiler operations.