Question

1. What different information about sterility comes from a chemical indicator and a biological indicator? 2. What conditions are necessary to guarantee sterility via steam sterilization? 3. What steps are required to verify both contact with the sterilant and sterilization of an instrument set?

Answer 1

1.Biological indicator is a product used for testing the efficiency of a sterilizer,the only method of guaranteeing an item is correctly sterilized.Bacillus Stearothermophilus is the bacterial spore used for the Biological indicator for steam sterilization,highly resistant to being killed by steam sterilization,but harmless to humans,test pack contains a vial of the microrganism in the spore stage impregnated on a disk.After sterilization cycle Biological indicator is taken out and crushed ,releasing growth medium and the broth is red in colour,if the liquid remains red the results are considered negative meaning the spores have been killed,if broth turns yellow it means the test was positive meaning conditions for sterilization were not met.

Chemical indicator is an internal or external monitor that changes colour when put through the sterilization process,changes colour when put through the sterilization process.it only validates that the package was exposed to a sterilent ,not that its sterile.it detect potential sterilization failuresthat may result from machine malfunction ,incorrect assembly or wrapping of package ,incorrect loading of the sterilizer cart or basket.The most popular type of external chemical indicator ,the tapeis used as a package closure to keep CSR wraps in place,prior to exposure the tape has evenly spaced diagonal lines of cream coloured ink,when the ink has been exposed it changes to black.Internal chemical indicators are placed in the area of package or tray where there is the greatest chance of entrapped air ,read when the package or tray is opened at the time of use.

2 Time,contact ,temperature,moisture and pressure are the conditions necessary to guarantee sterility via steam sterilization.

3 the steps required to verify both contact with the sterilant and sterilization of an instrument set are

• Immerse in warm water.
• Detergent enzyme cleaner with a neutral ph must be cleaned with back to back motion .
• Rinse in distiller water.
• Immediately dried to avoid spotting.