Which of the following is listed under 20 minutes?

• A. Dressings loosely packed
• B. Muslin fabric
• C. Wrapped or covered instruments
• D. Liquids

Answer: (C)

In sterile technique, sterility is maintained by the packaging and by staying within a time window after the field is set up. Wrapped or covered instruments are designed to keep their contents sterile for a short period, often up to about 20 minutes, as long as the wrapper remains intact and the field isn’t contaminated. That protection makes them the best fit for the 20-minute guideline.

Dressings loosely packed aren’t sealed and can harbor contaminants as soon as they’re exposed, so they don’t reliably stay sterile for a 20-minute window. Muslin fabric is porous and can shed fibers and allow microbes to pass through, compromising sterility over time. Liquids are easily contaminated once opened and are generally used immediately, not kept in a field for 20 minutes.

So wrapped or covered instruments align with the idea of maintaining sterility for a short, defined period within the sterile field.