CRCST Decontamination 3 — Questions and Answers
Question 1: Which type of washer-disinfector uses a thermal disinfection cycle as defined by the A0 concept?
- Ultrasonic washer
- Thermal washer-disinfector (automated) (Correct answer)
- Chemical immersion washer
- Cart washer only
Correct answer: Thermal washer-disinfector (automated)
Automated thermal washer-disinfectors use the A0 concept, which measures the lethal effect of heat on microorganisms at a reference temperature of 80°C.
Question 2: What hazard is associated with using high-pressure air to dry instruments in the decontamination area?
- It may cause instrument rust if prolonged
- It can aerosolize pathogens and contaminate the environment (Correct answer)
- It is too slow to be effective for drying
- It damages instrument surface coatings
Correct answer: It can aerosolize pathogens and contaminate the environment
Using compressed air to blow off water can aerosolize infectious droplets, creating an inhalation hazard for CS staff.
Question 3: Which term describes the physical removal of foreign material (soil, blood, tissue) from instruments, which is NOT sterilization?
- Disinfection
- Cleaning (Correct answer)
- Sanitization
- Pasteurization
Correct answer: Cleaning
Cleaning is the physical removal of soil and foreign material; it reduces the microbial load but is not the same as sterilization or disinfection.
Question 4: Why is it important to keep instrument sets submerged below the water surface in an ultrasonic cleaner?
- To prevent instruments from floating out and getting lost
- To ensure cavitation action reaches all surfaces and to prevent aerosol generation (Correct answer)
- To maintain water temperature more effectively
- To allow detergent to dissolve completely
Correct answer: To ensure cavitation action reaches all surfaces and to prevent aerosol generation
Keeping instruments below the water surface ensures full cavitation exposure and prevents contaminated aerosols from being released into the air.
Question 5: A CS technician notices a brown discoloration on stainless steel instruments after washing. This is most likely caused by:
- Improper detergent concentration
- Hard water minerals or inadequate rinsing (Correct answer)
- Exposure to gamma radiation
- Use of enzymatic cleaner at too high a temperature
Correct answer: Hard water minerals or inadequate rinsing
Brown discoloration (staining) on stainless steel is most often caused by mineral deposits from hard water or inadequate rinsing after washing.
Question 6: When transporting soiled instruments from the OR to the decontamination area, containers must be:
- Open-top trays for easy access
- Closed, leak-proof containers labeled as biohazardous (Correct answer)
- Wrapped in sterile towels to prevent drying
- Placed in clear bags without labels
Correct answer: Closed, leak-proof containers labeled as biohazardous
Soiled instruments must be transported in closed, leak-proof containers with biohazard labeling to prevent staff exposure and environmental contamination.
Question 7: The decontamination area should maintain a negative air pressure relative to adjacent areas. Why?
- To keep the area cooler for instrument storage
- To prevent contaminated air from flowing into clean processing areas (Correct answer)
- To maintain humidity for instrument soaking
- To comply with HVAC energy regulations
Correct answer: To prevent contaminated air from flowing into clean processing areas
Negative air pressure in the decontamination area ensures airflow moves inward, preventing potentially contaminated air from migrating to clean or sterile areas.
CRCST Decontamination 3
Which type of washer-disinfector uses a thermal disinfection cycle as defined by the A0 concept?