What is the purpose of the test lever fitted on each Pressure Safety Valve (PSV)?

The test lever fitted on each Pressure Safety Valve (PSV) is primarily used to assist in bench testing during calibration. This lever allows technicians to simulate the conditions under which the valve would actuate. By utilizing the test lever, one can verify that the valve opens at the appropriate set pressure, ensuring that it will function correctly in an actual overpressure situation.

This is crucial for maintaining system safety and integrity, as the PSV is designed to protect against excessive pressure that could lead to equipment failure or hazardous conditions. Properly testing and verifying the function of the PSV using the test lever supports compliance with safety standards and regulations.

The other choices do not accurately reflect the primary purpose of the test lever, as it does not function for visual inspections during operation, control exhaust pressure, or regulate steam flow. Each of these functions relates to different aspects of pressure and flow management but does not involve the specific role of the test lever in validating the performance of a pressure safety valve.