How often should the gauge used to set the regulated source of pressure on an extinguisher be calibrated?

The gauge used to set the regulated source of pressure on an extinguisher should be calibrated annually. Regular calibration is essential to ensure that the gauge provides accurate pressure readings, which are crucial for the effective operation of the extinguisher. If the pressure is too low or too high, it may compromise the extinguisher's effectiveness in an emergency situation. Annual calibration helps to maintain the reliability and safety of fire extinguishers, aligning with industry standards and best practices for fire safety equipment maintenance.