Monitoring and maintaining a safe operating water level on any steam boiler plant is an important part of the control area operator’s job function. There are specific minimum requirements for water level instrumentation that are documented in Section I of the ASME Boiler and Pressure Vessel (BPV) code.
Furthermore, a plant owner or insurance carrier may specify additional water level monitoring instrumentation to be installed beyond the minimum requirements. This way, the boiler can remain in compliance during operation, even if any single level indicating instrument is out of service for maintenance.