There are some things that hold true to every autoclave that you need to know.
Spore tests: Spore tests with biological indicators must be performed once a week. The indicator tape and indicator bags are only an aid. They cannot be relied upon to guarantee that your sterilizer is actually killing spores. The use of a third party to process the strips is highly recommended. If you are processing your own spore test strips, I still recommend a third party be used at least monthly. If at any time litigation is instituted, the documentation from a third party is invaluable.
To do a spore test correctly, the test strip should be inside of a pack or autoclave paper wrap. If your testing facility provides two strips, one wrapped and one loose are acceptable. After the test cycle is complete, remove the test strips and immediately mail them to the test lab. Before touching the strips, be sure they are dry. The type of paper that the test strips are enclosed in will transfer germs if it is wet. It is even better to handle the strips with a sterilized instrument, picking them up by the very end of the paper envelope.
Use only distilled water in steam sterilizers. Make sure the water is steam-distilled. There are distilling techniques that use methods other than steam distillation, but these methods are not to be trusted unless tested for the absence of total dissolved solids with a reliable testing device.
Steam leaks: Try to observe your autoclave during cycles whenever possible. If you see steam leaks around the door, you probably are not obtaining adequate sterilization pressure. Clean the surface where the door gasket makes contact. If the leaks persist, replace the gasket.
How long must the cycle last? This question is often asked of service personnel ... and the answer is frequently challenged! The time needed is contingent on optimum performance of the sterilizer. The required time to achieve sterilization hinges on adequate temperature, as well as pressure for the entire cycle. At sea level, unwrapped instruments should be sterilized at 270 F (132 C) and 28 psi for at least three minutes. Wrapped instruments should be sterilized for at least 12 minutes. This information applies to steam sterilizers. Chemical vapor and dry-heat sterilizers require more time.
What if you get a positive (failed) spore test? As soon as you get word from your testing facility, you should do another test. This time, you need to monitor the autoclave during the cycle. Make sure that it is getting up to the required temperature and pressure.
When the cycle is complete, allow the test strips to dry before moving them to the mailing envelope. (Most failed tests are the result of careless handling of the test strips.) If your autoclave is reaching the required parameters - and is maintaining those parameters for the entire cycle - sterilization should be achieved. If the temperature and/or pressure are dropping off during the cycle, do not keep using the autoclave. Call for service help and get a backup sterilizer!
Speaking of "backups" ... How important is it to have sterilized instruments? If your autoclave should go down, do you have a contingency plan? Maybe a small second sterilizer is just what you need. Are there two or three other dentists close by? Perhaps a "community" backup might be a feasible option.
Dave Cheney is a retired service technician from Patterson Dental with over 30 years in the dental industry. He is the author of "Doctor, Did You Check the Breaker, Too?" a manual written to assist the dental staff in analyzing and performing minor equipment repairs when a technician is not warranted or not readily available. To order the manual as a book or CD, call (800) 695-0943. You may also order it online through his Web site at www.davandental.com.
