Which alarm should always be set to alert staff about the potential risk of running out of water?

The holding tank low level alarm is crucial for notifying staff about the potential risk of running out of water because it directly monitors the water supply in the holding tank. This alarm triggers when the water level drops below a pre-determined threshold, providing an early warning that action needs to be taken to avoid a complete depletion of water. By setting this alarm, staff can ensure that there is a continuous supply of water for the system, which is essential for its proper functioning and to avoid operational disruptions.

Other alarms, such as the flow alarm, pressure alarm, and high TDS alarm, serve different purposes. The flow alarm may alert operators to issues with water movement through the system, the pressure alarm monitors the system's operating pressure, and the high TDS alarm indicates an increase in total dissolved solids, which can affect water quality but does not directly indicate the level of water supply. Therefore, while all alarms are important, the holding tank low level alarm specifically addresses the immediate concern of maintaining adequate water levels.