Answer
A Master Gauge is a high-precision, primary standard measuring instrument used strictly as a reference standard onboard ship and in engineering workshops.
- Purpose: It is not used for daily operational checks. Its sole purpose is to calibrate, test, and verify working instruments (such as working pressure gauges, temperature calibrators, micrometres, or torque wrenches).
- Characteristics:
- Maintained under controlled conditions in a protected storage space.
- Accompanied by a valid calibration certificate from a recognized calibration laboratory/testing authority (traceable to national or international standards).
- Recalibrated periodically as mandated by the ship's Safety Management System (SMS) and PMS schedules.