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Center for Professional Practice of Nursing

Center for Professional Practice of Nursing

The sterilization process

Cleaned devices are placed in the appropriate tray or container, which is positioned in the processor. The processor is designed to accept these interchangeable trays and containers to hold the many different types of instruments and ensure that these instruments are correctly positioned for processing. Lumened devices, such as endoscopes, are attached to specific trays with special connections to allow fluid to flow through the internal channels.

A cup containing the 35 percent PA solution in the inner cup and the powdered buffers in the outer cup is placed in the processor. A cup-cutter in the bottom of the sterilant compartment penetrates through the bottom part of the cup to release the buffers during processing. A probe with a spike (aspirator probe) is inserted into the top of the sterilant cup, while the probe tubing is positioned appropriately so that the PA can be siphoned out of the cup during the process. The processor lid is then closed and the system is activated by pushing the start button. When the start button is pushed, the microprocessor takes control. The buffers mix with water to form the chemical protection system. The active ingredient, PA, is brought into solution at the appropriate time.

Sterilization takes place between 50 and 56 degrees Centigrade, which is safe for heat-sensitive devices. The use dilution comes in contact with accessible external and internal surfaces of the instruments. Exposure to the use dilution lasts for 12 minutes and is followed by four sterile water rinses to remove any sterilant residues. The end products of acetic acid (vinegar), water, and oxygen are safely disposed of in the normal sanitary sewer system without environmental concerns.

The entire processing cycle is completed in 30 minutes. The sterilized devices are removed from the system for immediate use. Processing trays are available that incorporate tortuous pathways to protect sterile instruments from contamination during transport.

Next: Process Monitoring