RML 2023
Applied Microbiology & Infection control
Easy

Which is a correct statement regarding autoclaving?

Appeared in: RML 2023

Explanation

  • Autoclaving is a sterilization process that utilizes moist heat in the form of saturated steam.
  • The process is conducted under high pressure, which allows the steam to reach temperatures above the normal boiling point of water (typically 121°C).
  • This combination of high-temperature moist heat is extremely effective at killing all forms of microbial life, including highly resistant bacterial spores.
  • The mechanism of killing is the denaturation and coagulation of essential proteins within the microorganisms.

Why Other Options Were Wrong

  • Option A: This is incorrect because autoclaving uses moist heat (steam), not dry heat. Dry heat sterilization is a separate method, typically performed in a hot air oven.
  • Option B: This is incorrect for the same reason as the first option; autoclaving relies on moist heat, not dry heat.
  • Option D: This is incorrect because autoclaving requires high pressure to raise the steam's temperature to the effective sterilization level of 121°C. Low pressure would not achieve this temperature.

Related Visual

Visual explanation — Related Visual
Clinical Relevance
  • Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Principle of Autoclaving as background academic context rather than a clinical decision trigger.
  • Autoclaving is the most common and reliable method of sterilization used in hospitals for surgical instruments, dressings, and other medical equipment to prevent healthcare-associated infections (HAIs).
  • Nurses are responsible for ensuring that equipment is properly prepared, loaded, and monitored during the autoclaving cycle. This includes using chemical and biological indicators to verify sterility.
  • What if? - If an autoclave fails to reach the required pressure (e.g., due to a leak in the door seal), it will also fail to reach the target temperature of 121°C. This would result in an incomplete sterilization cycle, and the items would not be sterile and must not be used on patients.
How to Approach the Question
  • First, identify the key term in the question, which is 'autoclaving'.
  • Recall the definition and fundamental principle of autoclaving from your knowledge of microbiology and infection control.
  • Analyze the options by breaking them down into two components: the type of heat (moist vs. dry) and the level of pressure (high vs. low).
  • Remember that 'auto' relates to self and 'clave' to key or lock, implying a sealed, pressurized chamber. Steam is water in its gaseous form (moist heat).
  • Eliminate the 'dry heat' options, as autoclaving is synonymous with steam sterilization.
  • Between the remaining 'moist heat' options, recall that pressure is increased to raise the temperature, so 'under pressure' (implying high pressure) is correct, and 'low pressure' is incorrect.
Concept Tested & Keywords
  • Concept Tested: Principle of Autoclaving
  • Stem keywords: autoclaving, correct statement, principle
  • Lead-in keywords: Which is
  • Negative lead-in flag: false

Question ID

QTUVRmRJqInresd-ocYP3V

Reference Book

E6 Parks TextBook of Preventive & Social Medicine part 1 — Subpart A (pp 26-201 of 604) p. 127-129

Practise the full RML 2023

Attempt every question from this paper in a timed mock, then review the full solution for each one.

More Disinfection and Sterilization Questions

More RML 2023 Questions