Spotlight on Standards: Report Highlights Importance of Water Quality in Reprocessing

April 7, 2017

Categories: AAMI News

Water QualityOne of the key ingredients for successful reprocessing of reusable medical devices is all around us—water.

“The quality of water should not be taken for granted,” said Jacqueline Daley, manager of infection prevention, clinical epidemiology, and vascular access at Sharp Memorial Hospital in San Diego, CA. “Water with high levels of mineral impurities and bacteria can adversely affect patient outcomes. Over time, these bacterial contaminants can lead to the formation of biofilm, and minerals can interact with detergents, interfering with their effectiveness.”

According to an AAMI technical information report, TIR34, Water for the reprocessing of medical devices, “The water used to reprocess a medical device needs to be of sufficient quality to ensure that the device is not damaged and that the patient will not be injured by contact with the device.”

This means that sterile processing departments (SPDs) need to know what they are working with, according to Emily Mitzel, technical consulting manager at Nelson Laboratories.

“Water from the public utility source should be analyzed by an accredited facility with expertise in water quality to determine whether the water requires treatment and, if so, what type of treatment,” Mitzel said. Such treatment can include processes such as reverse osmosis, deionization, and distillation.

However, not every stage of reprocessing requires the same level of quality.

“Water quality plays a key role in all stages of instrument processing—cleaning, rinsing, disinfection, and sterilization—but various stages of instrument and device processing require a different quality of water,” Daley explained. “For example, water used to clean contaminated devices can be tap water, but water used for the final rinse of items for sterilization or high-level disinfection requires a higher quality to reduce the risk of infection and the risk of pyrogenic reactions from high quantities of endotoxin.”

TIR34 identifies two categories of water that are important for medical device reprocessing:

  • Utility: Water from the tap that is usually used for flushing, washing, and rinsing.
  • Critical: Water that has been extensively treated so it can be used during the final rinsing stage or steam sterilization.

“AAMI TIR34 gives very specific instructions on what type of water quality should be used at each stage of reprocessing, how to build the water treatment systems, and how to test for the correct water quality for both utility and critical water sources,” Mitzel said.

“It is critical that the SPD management and staff understand the importance of water quality and work closely with their facilities engineer to ensure that they are fully aware of what is happening with the water supply,” Daley added. “This knowledge comes in handy when troubleshooting and problem solving issues that arise with instruments, devices, and sterilization and automated reprocessing equipment as a result of inadequate water quality.”

AAMI TIR34, Water for the reprocessing of medical devices

  • List: $222
  • Member Price: $131
  • Order Code: TIR34 or TIR34-PDF

To order, call 1-877-249-8226 or visit

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