CER Cheat Sheet 2026

The 30 highest-yield CER facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. When connecting an endoscope to an AER, which action is most critical for ensuring effective channel reprocessing? → Attaching all channel connectors according to the manufacturer's IFU
2. What action should be taken if the endoscope fails the leak test? → Remove the scope from service and send for repair before further use
3. What does "deflection" refer to in the context of flexible endoscopes? → The ability of the endoscope tip to bend
4. Which route of transmission is most commonly associated with endoscope-related infections? → Contact transmission via the contaminated endoscope's channels and surfaces
5. Which tool is used to inspect the biopsy channel interior of a flexible endoscope for retained soil? → Channel inspection scope (mini-endoscope) or borescope
6. Which document must manufacturers of FDA-cleared HLD chemicals provide that outlines validated reprocessing instructions for specific endoscope models? → Instructions for Use (IFU)
7. Which sterilization method uses 100% ethylene oxide in a single-dose cartridge system? → 3M Steri-Vac or Anprolene single-use ETO systems
8. What does MEC stand for in the context of high-level disinfectant testing? → Minimum Effective Concentration
9. What is the maximum recommended relative humidity for endoscope storage? → 60%
10. What does "IFU" stand for in the context of medical device reprocessing? → Instructions For Use
11. What type of cleaning solution should NEVER be used on the exterior of an endoscope? → Alcohol-based solutions on rubber or silicone components
12. Which microorganism is most associated with outbreaks linked to inadequate AER water quality? → Pseudomonas aeruginosa
13. Which area of the body is a gastroscope designed to view? → Stomach
14. Under Joint Commission standards, what must be documented after every endoscope reprocessing cycle? → Scope identifier, reprocessing method, operator, date, and MEC test results
15. Which storage method creates the highest risk of endoscope recontamination? → Horizontal coiled storage in an enclosed, unventilated cabinet
16. What is the Spaulding classification for a flexible gastroscope used to examine the stomach? → Semi-critical — requires high-level disinfection
17. Which regulatory body has the authority to issue a 483 Observation or Warning Letter to an endoscope reprocessing facility? → FDA
18. Which of the following is a key preventive maintenance practice performed by reprocessing staff to avoid costly repairs to the light guide connector? → Attaching the waterproof cap securely before any immersion in fluids.
19. Which chemical disinfectant is known to fix proteins to endoscope surfaces if used before adequate cleaning? → Glutaraldehyde
20. How should reusable cleaning brushes be managed after each use during endoscope reprocessing? → Discard after each patient use or reprocess according to manufacturer IFU
21. What is the maximum recommended storage time for a reprocessed endoscope before it must be reprocessed again? → Per manufacturer and facility policy, generally 5–7 days in a validated drying cabinet
22. Before placing an endoscope into an AER, which step must always be completed first? → Manual cleaning and leak testing
23. Which finding during visual inspection would indicate that an endoscope requires repair before further use? → A crack or abrasion in the insertion tube sheath
24. How should the exterior of a flexible endoscope be cleaned during manual cleaning? → Wiped from distal to proximal end with a single lint-free cloth soaked in detergent
25. In a video endoscope, how is the image transmitted from the distal tip to the processor? → Via a charge-coupled device (CCD) or CMOS sensor and electrical cable
26. Which document provides the primary guidance for validating AER cycles for endoscope reprocessing in the US? → ANSI/AAMI ST91
27. When should endoscopes stored on open pegs or hooks without a cabinet be considered for reprocessing? → Per facility policy, but typically within 24–48 hours for unsupported open storage
28. What is biofilm in the context of endoscope reprocessing? → A collection of microorganisms that attach to surfaces and form a colony
29. According to the AAMI ST91 standard, what is the ideal number of sinks for the decontamination area, and what are their designated purposes? → Three sinks: one for leak testing, one for manual cleaning/washing, and one for rinsing.
30. Which of the following best describes the correct order of the first three steps in flexible endoscope reprocessing? → Pre-clean at point of use → Leak test → Manual clean with detergent