Sterile Processing Department.
Biomed Managers.



Wet Packs and SPD - Troubleshooting

Sterilizers and autoclaves are critical components in health care, life sciences, institutional, and research facilities... but since they are open-ended steam users, poor steam quality (water in the line) can cause major problems.

We perform steam quality testing according to ANSI/AAMI ST79, Comprehensive guide to steam sterilization and sterility assurance in health care facilities (2010), and European Standard EN285.

If you are experiencing wet packs, there are some basic troubleshooting steps you can take:

  1. Start a list of the wet items, make a note of time, type of sets (especially heavy ortho sets). Steam loads change hourly with a typical healthcare system. Weather, time of day, changes to water treatment, can impact wet steam and create wet loads… So, good documentation and communication will help diagnose any future wet load occurrences.
  2. Make sure the sets are not overweight. Sterilizers built before 2010 are usually only validated for 17 pound sets. After 2010, SOME sterilizers are validated for 25 pound sets. Make sure you are weighing your sets.
  3. There is a good checklist in the Amendment 4 of the ST-79 Standard. This amendment came out in 2014, so you might only have a PDF of it, or it is stuffed in the back of the AAMI binder if you have hard copy.
  4. If basin sets are the primary culprit, read this discussion on basin sets

You can also read some of our articles about sterilizer wet packs, stains, and steam quality:

Thermo Diagnostics Services


What does industry say about sterilizers and wet pack problems?

"Perhaps the most frustrating and confounding dilemma that we face using steam sterilization is the occurrence of wet packs...

"Wet packs represent an economic loss to the institution because goods must be reprocessed. Unrecognized, they are a hazard to the patient."
- Preparing instruments, utensils and textiles for sterilization and wet pack solving, STERIS Inc. 2003.



Eliminate Steam Problems.

Thermo Diagnostics will work with your facility engineers to eliminate steam problems. This saves cost, time, effort and reduces staff complaints. Reduced "reprocessing" will improve productivity, service, and morale. The net result will be increased efficiency and quality of facility management.

How is Steam Quality Testing related to Wet Pack Troubleshooting?

ST-79 and EN-285 procedures develop data, and we test according to those procedures. What makes us different is we also test the rest of the valves, insulation, boiler piping and water supply that can impact steam quality.

You rely on the system to deliver steam that is clean, dry, and sterile... do you figure out what's causing the problems? That's our job.

Independent, Confidential, Experienced.

We are not affiliated with any sterilizer or humidifier manufacturer.
Our audit staff average 30 years experience with steam in hospitals and life sciences.

Theme Diagnostics

Thermo Diagnostics Company LLC

Steam System Consulting.
PO Box 2760 - West Lafayette, IN 47996-2760
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