To describe a standard operating procedure for the calibration of vacuum gauges. The standard operating procedure describes in detail the method for the calibration of vacuum gauges in the plant. The responsibility of calibrating the gauges lies with the staff of rank not lower than the supervisor of maintenance department. The responsibility of preparation, review and approval of the standard operating procedure lies with the Manager (Maintenance), Head of Production and Head of QAD respectively. Vacuum Gauges , Engineering, U-Tube Manometer