Pre-Loading Core Inspections
Before loading a vertical pressure steam sterilizer, three critical inspections must be performed. First, verify equipment calibration: confirm that the pressure gauge, temperature gauge, and safety valve are within their calibration validity period, typically recalibrated every 6 months, to avoid parameter errors from measurement deviations. Second, inspect the sealing ring integrity: check the silicone sealing ring for aging, cracks, or foreign residue such as culture medium deposits, as seal failure will cause unstable chamber pressure. Third, perform item pre-treatment: liquid reagents require leaving 10 percent volume space to prevent boiling overflow; hollow instruments such as syringes and pipettes should be filled with water or have vent holes opened; dressings and wraps should be moderately tight, as excessive tightness blocks steam penetration while looseness risks unraveling.
Loading Procedures and Requirements
Loading must follow four key rules to ensure effective sterilization. The loading volume must not exceed 80 percent of chamber capacity to avoid obstructing steam circulation. A minimum 2 centimeter gap must be maintained between items, and stacking is not allowed. Liquid containers should be placed on lower shelves to prevent overflow contamination of upper items, while solid instruments should have joints opened and be placed flat. No items should contact chamber walls or the door. Glassware must be isolated with silicone pads to prevent collisions and breakage during the sterilization cycle.
Parameter Settings by Material Type
Sterilization parameters must be strictly matched to item types. Culture media and liquid reagents require 121 plus or minus 1 degree Celsius for 15 to 20 minutes with slow exhaust at 0.1 MPa per minute or less. Metal instruments and glassware require 132 plus or minus 1 degree Celsius for 4 to 6 minutes with fast exhaust at 0.2 MPa per minute or less. Dressings and packaged items require 121 plus or minus 1 degree Celsius for 20 to 30 minutes with slow exhaust. An empty chamber performance test should be conducted once per month at 121 plus or minus 1 degree Celsius for 10 minutes to verify temperature distribution uniformity.
Sterilization and Exhaust Management
After starting the device, exhaust for 3 to 5 minutes to remove cold air. Cold air residue creates cold spots with temperatures 5 to 10 degrees Celsius lower than the set point, causing sterilization failure. During the sterilization phase, monitor temperature and pressure fluctuations, which should remain within plus or minus 1 degree Celsius and plus or minus 0.02 MPa. If fluctuations exceed these limits, stop the equipment and inspect immediately. After sterilization ends, wait until chamber pressure drops to 0 MPa. Liquids require an additional 15 to 20 minutes of cooling while solids need 10 to 15 minutes. Open the door slowly to avoid high-temperature steam bursts. After removal, verify that the 3M chemical indicator card has completely changed color to deep black.
Record Keeping and Maintenance
All operations must be recorded synchronously, including date, time, item type, set parameters, actual parameters, and operator signature. Records must be retained for at least 12 months to meet CNAS and other qualification audit requirements. Regular maintenance includes daily self-checks using a standardized checklist, monthly empty chamber performance testing, and calibration of pressure gauges and temperature sensors every 6 months.
