What safety device is required to be located at the boiler steam outlet?

The safety device that is required at the boiler steam outlet is a safety valve. A safety valve is a critical device designed to protect the boiler from exceeding its maximum allowable working pressure. If pressure within the boiler builds up beyond safe limits, the safety valve automatically opens to release steam, thereby lowering the pressure and preventing potential hazardous situations such as an explosion or equipment failure. Thus, the presence of a safety valve at the steam outlet is essential for safe boiler operation.

In this context, other devices like water level gauges, pressure gauges, and temperature sensors serve different purposes. A water level gauge monitors the water level inside the boiler, ensuring sufficient water is present to produce steam. A pressure gauge indicates the current pressure of the steam inside the boiler but does not provide pressure relief. A temperature sensor measures the temperature of the steam but does not directly manage pressure. Therefore, while these devices are important for monitoring and operational purposes, they do not fulfill the specific safety role of pressure relief that is the primary function of a safety valve at the steam outlet.