Question

For sterilization, the culture media and glasswares must be generally autoclaved at:

• A. 121\(^\circ\)C and 19 psi
• B. 121\(^\circ\)C and 15 psi
• C. 112\(^\circ\)C and 15 psi
• D. 120\(^\circ\)C and 20 psi

Hint:

The combination of \textbf{121\(^\circ\)C} and \textbf{15 psi} is the universal standard for autoclaving in microbiology labs. Memorize this pair of values as they are fundamental to sterilization protocols.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
Autoclaving is a sterilization process employing high-pressure saturated steam to eradicate all microorganisms, including resilient bacterial endospores, from materials. This necessitates precise temperature, pressure, and duration.
Step 2: Detailed Explanation:


Laboratory autoclaves typically operate at conditions designed to eliminate the most heat-resistant bacterial spores.

To reach a steam temperature of 121\(^\circ\)C (250\(^\circ\)F), the pressure must exceed standard atmospheric levels.

The usual pressure to achieve 121\(^\circ\)C is about 15 psi (pounds per square inch) above atmospheric pressure.

Maintaining these conditions (121\(^\circ\)C, 15 psi) for at least 15-20 minutes is crucial for thorough sterilization; the precise duration depends on the load's size and characteristics.

Step 3: Final Answer:
The commonly accepted standard autoclaving parameters are 121\(^\circ\)C and 15 psi.