Instrument milk

Sterile processing definition

Instrument milk is a water-soluble lubricant applied to hinged instruments after cleaning to keep box locks and joints moving freely. It is used instead of mineral oil or silicone spray because a water-soluble lubricant lets steam reach the metal surface, while oils can block sterilant contact.

On the CRCST exam

Know why water-soluble lubricant is used: it doesn't block the sterilant.

Exam domain: Preparation & Packaging (about 21% of the exam)

Preparation & Packaging practice questions

Packaging for hydrogen peroxide gas plasma sterilization
Loaner trays cleaned at another facility
Prep and pack area air pressure
Why instrument milk is used instead of oil

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