Certified Endoscope Reprocessor CER Exam 2026 Latest
Comprehensive Study Guide with Practice Questions
Endoscope Reprocessing Review, Detailed Rationales,
Verified Answers, Success Workbook
1. A flexible endoscope has been used in a procedure and is ready for
reprocessing. What is the FIRST step the reprocessing technician should
perform?
A) Transport the scope to the decontamination area immediately
B) Perform a leak test before any cleaning
C) Perform point-of-use pre-cleaning at the bedside or procedure site
D) Place the scope in an automated endoscope reprocessor (AER)
Rationale: The correct answer is C) Perform point-of-use pre-cleaning at
the bedside or procedure site. Point-of-use pre-cleaning is the first step in
the endoscope reprocessing workflow. This involves wiping the exterior of the
insertion tube with a soft cloth or sponge moistened with enzymatic
detergent, flushing the channels with enzymatic detergent, and aspirating
fluids through the suction channel. This immediate action prevents soil and
debris from drying on the scope, which can lead to biofilm formation and
make subsequent cleaning more difficult. Pre-cleaning must be performed
immediately after the procedure before the scope is transported.
2. A technician is preparing to perform a leak test on a flexible
endoscope. According to ANSI/AAMI ST91, when should the leak test be
performed?
A) Only if the scope was used in a contaminated procedure
B) Before manual cleaning, while the scope is still dry
C) After manual cleaning, before high-level disinfection
D) Only when the scope is connected to an automated leak tester
Rationale: The correct answer is B) Before manual cleaning, while the
scope is still dry. Leak testing must be performed before the scope is
,immersed in any liquid. If the scope has a leak, immersing it could allow fluid
to enter the internal channels, causing damage to delicate components and
creating a reservoir for microorganisms. The leak test detects breaches in the
channel or sheath that could harbor bacteria or fluids. If a leak is detected, the
scope should not be immersed and must be handled according to the
manufacturer's instructions for use (IFU) and facility protocol.
3. During manual cleaning of a flexible endoscope, the technician notices
that the cleaning brush does not pass completely through the channel.
The technician should:
A) Force the brush through the channel
B) Stop, inspect the channel for obstructions, and follow IFU for clearing
blockages
C) Send the scope for high-level disinfection without complete cleaning
D) Use a smaller brush
Rationale: The correct answer is B) Stop, inspect the channel for
obstructions, and follow IFU for clearing blockages. If a brush cannot pass
completely through a channel, there may be an obstruction that must be
cleared before the scope can be safely reprocessed. Forcing the brush could
damage the channel lining. The technician should follow the manufacturer's
IFU for clearing blockages. Incomplete cleaning leaves organic material in the
channel, which can protect microorganisms from high-level disinfection and
lead to infection outbreaks.
4. A technician is performing manual cleaning of a flexible endoscope.
The brush should be:
A) Pulled back through the channel before rinsing
B) Rinsed before being pulled back through the channel
C) Used only once and discarded
D) Pulled through the channel in one direction only
Rationale: The correct answer is B) Rinsed before being pulled back
through the channel. When brushing the lumens of an endoscope, the brush
should be rinsed before pulling it back through the channel. This prevents
,debris that was picked up during the forward pass from being deposited
further back in the channel during the return pass. The goal is to remove soil,
not redistribute it. Brushes should be inspected for wear and replaced
according to IFU.
5. According to the Spaulding classification system, flexible endoscopes
that contact mucous membranes are classified as:
A) Critical items
B) Semi-critical items
C) Non-critical items
D) Disposable items
Rationale: The correct answer is B) Semi-critical items. The Spaulding
classification categorizes patient-care items based on the risk of infection.
Semi-critical items contact mucous membranes or non-intact skin and require,
at minimum, high-level disinfection (HLD). Flexible endoscopes that contact
mucous membranes (e.g., gastroscopes, colonoscopes, bronchoscopes) are
classified as semi-critical and must undergo high-level disinfection after
cleaning. Critical items (e.g., surgical instruments) penetrate sterile tissue and
require sterilization.
6. High-level disinfection (HLD) is defined as a process that:
A) Kills all microorganisms including bacterial spores
B) Kills all microorganisms except large numbers of bacterial spores
C) Kills only vegetative bacteria
D) Kills only viruses
Rationale: The correct answer is B) Kills all microorganisms except large
numbers of bacterial spores. High-level disinfection (HLD) eliminates all
microorganisms except high levels of bacterial spores. It is the minimum
standard for reprocessing semi-critical items such as flexible endoscopes.
Sterilization kills all microorganisms including spores. The distinction
between HLD and sterilization is a key concept in the Spaulding classification.
, 7. A technician is preparing to reprocess an endoscope that has been in
an extended soak (delayed reprocessing). What additional step may be
required?
A) No additional steps are needed
B) Extended soaking may require additional cleaning time and/or the
use of an enzymatic foam or gel to prevent drying
C) The scope should be discarded
D) The scope should be sterilized instead of disinfected
Rationale: The correct answer is B) Extended soaking may require
additional cleaning time and/or the use of an enzymatic foam or gel to
prevent drying. When reprocessing is delayed and the scope is soaked, the
manufacturer's IFU may specify extended soak indications and requirements.
Enzymatic foam or gel may be used to keep the scope moist and prevent soil
from drying on the surfaces. The specific requirements depend on the scope
manufacturer's IFU and facility protocol.
8. During high-level disinfection, which of the following factors can
influence the effectiveness of the process?
A) The color of the disinfectant
B) Expired disinfectant, expired test strips, and diluted disinfectant
C) The brand of the disinfectant
D) The temperature of the room
Rationale: The correct answer is B) Expired disinfectant, expired test
strips, and diluted disinfectant. Factors influencing the high-level
disinfection process include expired disinfectant, expired test strips, diluted
disinfectant, and temperature. The effectiveness of HLD depends on using a
properly prepared disinfectant at the correct concentration, temperature, and
contact time. Test strips must be used to verify the minimum effective
concentration (MEC) of the disinfectant before each use. Expired or diluted
disinfectant will not achieve the required log reduction of microorganisms.
9. A technician is using an automated endoscope reprocessor (AER).
After the cycle completes, what should the technician do FIRST?
Comprehensive Study Guide with Practice Questions
Endoscope Reprocessing Review, Detailed Rationales,
Verified Answers, Success Workbook
1. A flexible endoscope has been used in a procedure and is ready for
reprocessing. What is the FIRST step the reprocessing technician should
perform?
A) Transport the scope to the decontamination area immediately
B) Perform a leak test before any cleaning
C) Perform point-of-use pre-cleaning at the bedside or procedure site
D) Place the scope in an automated endoscope reprocessor (AER)
Rationale: The correct answer is C) Perform point-of-use pre-cleaning at
the bedside or procedure site. Point-of-use pre-cleaning is the first step in
the endoscope reprocessing workflow. This involves wiping the exterior of the
insertion tube with a soft cloth or sponge moistened with enzymatic
detergent, flushing the channels with enzymatic detergent, and aspirating
fluids through the suction channel. This immediate action prevents soil and
debris from drying on the scope, which can lead to biofilm formation and
make subsequent cleaning more difficult. Pre-cleaning must be performed
immediately after the procedure before the scope is transported.
2. A technician is preparing to perform a leak test on a flexible
endoscope. According to ANSI/AAMI ST91, when should the leak test be
performed?
A) Only if the scope was used in a contaminated procedure
B) Before manual cleaning, while the scope is still dry
C) After manual cleaning, before high-level disinfection
D) Only when the scope is connected to an automated leak tester
Rationale: The correct answer is B) Before manual cleaning, while the
scope is still dry. Leak testing must be performed before the scope is
,immersed in any liquid. If the scope has a leak, immersing it could allow fluid
to enter the internal channels, causing damage to delicate components and
creating a reservoir for microorganisms. The leak test detects breaches in the
channel or sheath that could harbor bacteria or fluids. If a leak is detected, the
scope should not be immersed and must be handled according to the
manufacturer's instructions for use (IFU) and facility protocol.
3. During manual cleaning of a flexible endoscope, the technician notices
that the cleaning brush does not pass completely through the channel.
The technician should:
A) Force the brush through the channel
B) Stop, inspect the channel for obstructions, and follow IFU for clearing
blockages
C) Send the scope for high-level disinfection without complete cleaning
D) Use a smaller brush
Rationale: The correct answer is B) Stop, inspect the channel for
obstructions, and follow IFU for clearing blockages. If a brush cannot pass
completely through a channel, there may be an obstruction that must be
cleared before the scope can be safely reprocessed. Forcing the brush could
damage the channel lining. The technician should follow the manufacturer's
IFU for clearing blockages. Incomplete cleaning leaves organic material in the
channel, which can protect microorganisms from high-level disinfection and
lead to infection outbreaks.
4. A technician is performing manual cleaning of a flexible endoscope.
The brush should be:
A) Pulled back through the channel before rinsing
B) Rinsed before being pulled back through the channel
C) Used only once and discarded
D) Pulled through the channel in one direction only
Rationale: The correct answer is B) Rinsed before being pulled back
through the channel. When brushing the lumens of an endoscope, the brush
should be rinsed before pulling it back through the channel. This prevents
,debris that was picked up during the forward pass from being deposited
further back in the channel during the return pass. The goal is to remove soil,
not redistribute it. Brushes should be inspected for wear and replaced
according to IFU.
5. According to the Spaulding classification system, flexible endoscopes
that contact mucous membranes are classified as:
A) Critical items
B) Semi-critical items
C) Non-critical items
D) Disposable items
Rationale: The correct answer is B) Semi-critical items. The Spaulding
classification categorizes patient-care items based on the risk of infection.
Semi-critical items contact mucous membranes or non-intact skin and require,
at minimum, high-level disinfection (HLD). Flexible endoscopes that contact
mucous membranes (e.g., gastroscopes, colonoscopes, bronchoscopes) are
classified as semi-critical and must undergo high-level disinfection after
cleaning. Critical items (e.g., surgical instruments) penetrate sterile tissue and
require sterilization.
6. High-level disinfection (HLD) is defined as a process that:
A) Kills all microorganisms including bacterial spores
B) Kills all microorganisms except large numbers of bacterial spores
C) Kills only vegetative bacteria
D) Kills only viruses
Rationale: The correct answer is B) Kills all microorganisms except large
numbers of bacterial spores. High-level disinfection (HLD) eliminates all
microorganisms except high levels of bacterial spores. It is the minimum
standard for reprocessing semi-critical items such as flexible endoscopes.
Sterilization kills all microorganisms including spores. The distinction
between HLD and sterilization is a key concept in the Spaulding classification.
, 7. A technician is preparing to reprocess an endoscope that has been in
an extended soak (delayed reprocessing). What additional step may be
required?
A) No additional steps are needed
B) Extended soaking may require additional cleaning time and/or the
use of an enzymatic foam or gel to prevent drying
C) The scope should be discarded
D) The scope should be sterilized instead of disinfected
Rationale: The correct answer is B) Extended soaking may require
additional cleaning time and/or the use of an enzymatic foam or gel to
prevent drying. When reprocessing is delayed and the scope is soaked, the
manufacturer's IFU may specify extended soak indications and requirements.
Enzymatic foam or gel may be used to keep the scope moist and prevent soil
from drying on the surfaces. The specific requirements depend on the scope
manufacturer's IFU and facility protocol.
8. During high-level disinfection, which of the following factors can
influence the effectiveness of the process?
A) The color of the disinfectant
B) Expired disinfectant, expired test strips, and diluted disinfectant
C) The brand of the disinfectant
D) The temperature of the room
Rationale: The correct answer is B) Expired disinfectant, expired test
strips, and diluted disinfectant. Factors influencing the high-level
disinfection process include expired disinfectant, expired test strips, diluted
disinfectant, and temperature. The effectiveness of HLD depends on using a
properly prepared disinfectant at the correct concentration, temperature, and
contact time. Test strips must be used to verify the minimum effective
concentration (MEC) of the disinfectant before each use. Expired or diluted
disinfectant will not achieve the required log reduction of microorganisms.
9. A technician is using an automated endoscope reprocessor (AER).
After the cycle completes, what should the technician do FIRST?
