Sterilization & Infection Control Flashcards
7 cards from real CST practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Sterilization & Infection Control flashcards as text
Which biological indicator organism is used to verify the efficacy of ethylene oxide (EO) sterilization?
Answer: Bacillus atrophaeus
Bacillus atrophaeus (formerly B. subtilis var. niger) spores are the standard biological indicator for ethylene oxide sterilization cycles.
The term 'bioburden' refers to:
Answer: The number of viable microorganisms on a device before sterilization
Bioburden is the total number of viable microorganisms contaminating an item prior to sterilization.
A sterile field is considered contaminated when:
Answer: Moisture soaks through a sterile drape to the surface below
Strike-through contamination occurs when moisture creates a pathway for microorganisms through a sterile drape to an unsterile surface below.
Which sterilization method is most appropriate for heat-labile endoscopes?
Answer: Low-temperature hydrogen peroxide gas plasma
Low-temperature hydrogen peroxide gas plasma (e.g., STERRAD) is used for heat-sensitive instruments like flexible endoscopes.
The purpose of the pre-vacuum (prevacuum) phase in a dynamic-air-removal steam sterilizer is to:
Answer: Remove air to allow steam penetration into porous loads
The prevacuum phase evacuates air from the chamber and load so steam can penetrate porous materials uniformly.
Standard contact time for high-level disinfection using 2% glutaraldehyde at room temperature is:
Answer: 20 minutes
A minimum of 20 minutes at room temperature in 2% glutaraldehyde is required to achieve high-level disinfection.
Which packaging material is NOT compatible with hydrogen peroxide gas plasma sterilization?
Answer: Paper/cellulose-based wraps
Cellulose-based materials (paper) absorb hydrogen peroxide, interfering with the plasma cycle and are therefore incompatible.