A Canadian hospital was not able to sterilize their instruments due to rust-colored stains found surrounding the surgical tools they were using. It was detected that the steam which was generated by two huge boilers (which they heat hospital and provide heat for the sterilizers) were the cause.
A few factors could have caused staining:
1) The autoclave’s steam trap, which collects excess steam, failed, which sent moisture into the sterilizer.
2) Ironically, laundry detergent is a culprit. The surgical tools are wrapped in clean linen; if the detergent hasn’t been 100-per-cent rinsed, it can cause a teatype stain when subjected to the temperatures and pressure in the autoclave.
3) The boiler’s chemicals, designed to prevent corrosion, can carry over into the steam and cause staining.
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