Final answer:
Instrument trays are considered (b) non-critical surfaces because they come into contact with intact skin and do not require sterilization, needing only to be clean and potentially disinfected.
Step-by-step explanation:
Current infection control guidelines of the Organization for Safety and Asepsis Procedures (OSAP) consider instrument trays to be non-critical surfaces. Non-critical items are those that may contact intact skin but do not penetrate sterile tissues or come into contact with mucous membranes.
These items include bed linens, furniture, crutches, stethoscopes, and blood pressure cuffs. They require cleaning to remove visible dirt and may also require disinfection depending on the level of contact with patients, but they do not need to be sterile.