CRCST COMPREHENSIVE
CERTIFICATION PREP EXAM 2026/2027
QUESTIONS AND ANSWERS
1. Which of the following microorganisms is most resistant to the sterilization process?
A. Lipid viruses
B. Vegetative bacteria
C. Fungal spores
D. Prions
Answer: D
Conceptual Explanation: Prions, the causative agents of Creutzfeldt-Jakob Disease (CJD),
are abnormally folded proteins that are highly resistant to standard sterilization methods
compared to spores or viruses.
2. In the decontamination area, what is the required number of air exchanges per hour?
A. 6
B. 20
C. 15
D. 10
,Answer: D
Conceptual Explanation: ANSI/AAMI standards require that the decontamination area
maintains a minimum of 10 air exchanges per hour under negative pressure to prevent the
spread of contaminants.
3. Which process is used by ultrasonic cleaners to remove soil from instruments?
A. Impingement
B. Passivation
C. Electrolysis
D. Cavitation
Answer: D
Conceptual Explanation: Ultrasonic cleaners use cavitation, where high-frequency sound
waves create microscopic bubbles that implode, creating a vacuum that pulls debris away
from instrument surfaces.
4. What is the recommended temperature range for the decontamination area?
A. 60°F to 65°F (16°C to 18°C)
B. 68°F to 73°F (20°C to 23°C)
C. 75°F to 80°F (24°C to 27°C)
D. 65°F to 70°F (18°C to 21°C)
B. 60°F to 65°F (16°C to 18°C)
, Answer: A
Conceptual Explanation: The decontamination area temperature should be kept between
60°F and 65°F to minimize microbial growth and ensure comfort for staff wearing heavy
PPE.
5. Which type of sterilization monitoring provides a direct measure of lethality?
A. Administrative monitoring
B. Chemical monitoring
C. Mechanical monitoring
D. Biological monitoring
Answer: D
Conceptual Explanation: Biological indicators (BIs) contain bacterial spores, providing
the only direct evidence that the sterilization process actually killed microorganisms.
6. When processing flexible endoscopes, what is the first step in the decontamination
process?
A. Manual cleaning
B. High-level disinfection
C. Alcohol flush
D. Leak testing
Answer: D
CERTIFICATION PREP EXAM 2026/2027
QUESTIONS AND ANSWERS
1. Which of the following microorganisms is most resistant to the sterilization process?
A. Lipid viruses
B. Vegetative bacteria
C. Fungal spores
D. Prions
Answer: D
Conceptual Explanation: Prions, the causative agents of Creutzfeldt-Jakob Disease (CJD),
are abnormally folded proteins that are highly resistant to standard sterilization methods
compared to spores or viruses.
2. In the decontamination area, what is the required number of air exchanges per hour?
A. 6
B. 20
C. 15
D. 10
,Answer: D
Conceptual Explanation: ANSI/AAMI standards require that the decontamination area
maintains a minimum of 10 air exchanges per hour under negative pressure to prevent the
spread of contaminants.
3. Which process is used by ultrasonic cleaners to remove soil from instruments?
A. Impingement
B. Passivation
C. Electrolysis
D. Cavitation
Answer: D
Conceptual Explanation: Ultrasonic cleaners use cavitation, where high-frequency sound
waves create microscopic bubbles that implode, creating a vacuum that pulls debris away
from instrument surfaces.
4. What is the recommended temperature range for the decontamination area?
A. 60°F to 65°F (16°C to 18°C)
B. 68°F to 73°F (20°C to 23°C)
C. 75°F to 80°F (24°C to 27°C)
D. 65°F to 70°F (18°C to 21°C)
B. 60°F to 65°F (16°C to 18°C)
, Answer: A
Conceptual Explanation: The decontamination area temperature should be kept between
60°F and 65°F to minimize microbial growth and ensure comfort for staff wearing heavy
PPE.
5. Which type of sterilization monitoring provides a direct measure of lethality?
A. Administrative monitoring
B. Chemical monitoring
C. Mechanical monitoring
D. Biological monitoring
Answer: D
Conceptual Explanation: Biological indicators (BIs) contain bacterial spores, providing
the only direct evidence that the sterilization process actually killed microorganisms.
6. When processing flexible endoscopes, what is the first step in the decontamination
process?
A. Manual cleaning
B. High-level disinfection
C. Alcohol flush
D. Leak testing
Answer: D
