Texas Class A Barber Written ExamSanitation, Disinfection, and SafetyMedium

A barber is using a disinfectant that requires a contact time of 10 minutes. If the barber cleans the tools at 9:00 AM, at what time will the tools be properly disinfected and ready for use?

  1. A9:10 AM
  2. B9:05 AM
  3. C9:09 AM
  4. D9:11 AM
Show answer & explanation

Correct answer: A. 9:10 AM

Contact time (also known as dwell time) is the specific amount of time a disinfectant must remain wet on a surface or immersed with a tool to be effective. If cleaning concludes at 9:00 AM, and a 10-minute contact time is required, the tools will be disinfected and ready for use at 9:10 AM.

Why the other options are wrong

  • B. 5 minutes is insufficient for a 10-minute contact time.
  • C. 9 minutes is insufficient for a 10-minute contact time.
  • D. 11 minutes is longer than required, but the earliest they are ready is at 10 minutes.

Disinfectant Contact Time

The specific duration a disinfectant must remain wet on a surface or in contact with an item to effectively kill target microorganisms.

  • Crucial for disinfectant efficacy.
  • Varies by product and target pathogens.
  • Must be strictly followed for proper infection control.

Memory trick: Clean it first, then wet it well, and let the clock tell.

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