NFPA-99 Practice Exam

What type of alarm indicator must be activated by a high water level sensor in an air receiver that uses liquid ring compressors?

1. Area

2. Local

3. Master

4. Pressure

The correct answer is: Local

In the context of an air receiver using liquid ring compressors, the activation of an alarm indicator by a high water level sensor is most appropriately a local alarm. Local alarms are designed to provide immediate, on-site notifications to personnel about conditions that require attention, such as high water levels, which could indicate potential malfunction or overfilling of the receiver. This prompt notification allows for quick action, reducing the risk of overflows and associated hazards. Since liquid ring compressors utilize water for their operation, monitoring the water level is crucial for maintaining system efficiency and safety. A local alarm ensures that operators or nearby personnel can respond quickly to mitigate any issues. While other types of alarms, like area or master alarms, may have their own applications, they are typically intended for broader notification across multiple systems or areas rather than providing immediate information to personnel present at the specific equipment. Pressure alarms are specific to monitoring pressure levels rather than water levels, thus not relevant in this scenario.