For effective sterilization in the autoclave, the temperature should be how much?

AIIMS Raipur NO- 2019 (shift 3rd)

Applied Microbiology & Infection control

Easy

Appeared in: AIIMS Raipur NO- 2019 (shift 3rd)

Explanation

Autoclaving utilizes pressurized steam to achieve a temperature of 121°C, which is above the normal boiling point of water.
This combination of high temperature and moist heat is necessary to destroy all forms of microbial life, including highly resistant bacterial endospores.
The standard cycle for effective sterilization is maintaining 121°C at 15 psi pressure for a minimum of 15 minutes.

Option A: 121 degrees Fahrenheit is approximately 49.4°C, a temperature that is far too low for sterilization and insufficient for most disinfection.
Option C: 100 degrees Fahrenheit is approximately 37.8°C, which is close to human body temperature. This temperature can promote the growth of many bacteria rather than killing them.
Option D: 100°C is the boiling point of water. While boiling kills most vegetative bacteria, it does not reliably eliminate bacterial spores. Therefore, it is classified as disinfection, not sterilization.

Clinical Relevance

Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain Principles of Autoclave Sterilization as background academic context rather than a clinical decision trigger.
Proper autoclave sterilization is a fundamental practice in infection control, critical for preventing healthcare-associated infections (HAIs), especially surgical site infections (SSIs).
Nurses play a key role in the sterilization process, including ensuring instruments are cleaned beforehand, packs are loaded correctly to allow steam penetration, and cycle parameters are monitored using chemical and biological indicators.
What if? If a biological indicator test (containing Geobacillus stearothermophilus spores) from an autoclave load is positive, it indicates a sterilization failure. The entire load must be considered non-sterile, recalled, and reprocessed. The autoclave must be investigated and serviced before further use.

How to Approach the Question

Identify the key terms in the question: 'autoclave' and 'effective sterilization'.
Recall that 'sterilization' means the elimination of all microbial life, including highly resistant bacterial spores.
Recognize that this requires conditions more intense than simple boiling, which occurs at 100°C. This immediately makes 100°C a less likely answer for sterilization.
Differentiate between the Celsius (°C) and Fahrenheit (°F) scales. Note that the Fahrenheit options (121°F ≈ 49°C; 100°F ≈ 38°C) represent temperatures that are too low.
Based on this, the only plausible option for achieving sterilization is a temperature above 100°C.
Select the option that matches the standard temperature for autoclaving, which is a core piece of knowledge in microbiology and infection control.

Concept Tested & Keywords

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