CNT Clean Technique Actual Exam Newest Complete
Questions And Correct Detailed Answers| Already
Graded A+
1. A nurse is preparing to insert an indwelling urinary catheter using clean technique. The patient
has a history of recurrent urinary tract infections. Which of the following actions is most critical
for reducing infection risk during this procedure?
A. Using a sterile catheter and sterile lubricant, but clean gloves for insertion
B. Applying an antiseptic solution to the perineum using a clean cotton ball
C. Opening the catheter kit and touching the inner surface of the sterile drape with clean hands
D. Performing hand hygiene, then donning sterile gloves before handling the catheter
Answer: D
Rationale: For indwelling catheter insertion, sterile technique is required to prevent introducing
pathogens into the bladder. Hand hygiene and sterile gloves are essential. Option A is incorrect because
clean gloves do not provide adequate barrier protection. Option B is incorrect because clean cotton
balls are not sterile and may introduce microbes. Option C is incorrect because touching the sterile
drape with clean hands contaminates the field.
2. A nurse is changing a surgical wound dressing using clean technique. The wound is healing by
secondary intention and has moderate serosanguinous drainage. Which of the following actions
demonstrates correct application of clean technique?
A. Using sterile gloves and a sterile dressing, but cleaning the wound with tap water
B. Using clean gloves and a clean dressing, and cleaning the wound with sterile saline
C. Using sterile gloves and clean dressing, and cleaning the wound with hydrogen peroxide
D. Using clean gloves and sterile dressing, and cleaning the wound with sterile saline
Answer: D
Rationale: For clean technique wound care, clean gloves protect the nurse, while sterile dressing and
sterile saline prevent contamination of the healing wound. Option A is incorrect because tap water is not
sterile. Option B uses clean dressing, which is not sterile and may introduce pathogens. Option C uses
hydrogen peroxide, which can damage tissue and is not recommended for routine wound cleaning.
3. A nurse is preparing to administer a blood transfusion. The patient has a central venous
catheter. Which of the following best describes the required aseptic technique for connecting the
blood tubing to the catheter hub?
A. Clean the hub with an alcohol swab for 5 seconds and allow to dry, then connect using clean gloves
B. Scrub the hub with a 70% alcohol pad for 15 seconds and allow to dry, then connect using sterile gloves
C. Wipe the hub with a chlorhexidine wipe for 10 seconds, then connect immediately using clean gloves
D. Use a new sterile cap on the hub without additional cleaning, then connect using sterile gloves
Page 1
,Answer: B
Rationale: Blood transfusions require sterile technique due to high infection risk. Scrubbing the hub for
15 seconds with alcohol and allowing it to dry ensures disinfection. Sterile gloves prevent
contamination. Option A's shorter scrub and clean gloves are insufficient. Option C's immediate
connection after chlorhexidine does not allow drying, reducing efficacy. Option D omits hub
disinfection, which is necessary even with a new cap.
4. A nurse is setting up a sterile field for a lumbar puncture. Which of the following actions would
most likely compromise the sterility of the field?
A. Placing the sterile drape on a clean, dry surface
B. Opening the outer wrapper of a sterile package before opening the inner wrapper
C. Allowing a sterile instrument to touch the edge of the sterile drape
D. Pouring sterile solution into a sterile basin from a height of 6 inches
Answer: C
Rationale: The edge of a sterile drape (typically 1 inch border) is considered contaminated because it
cannot be guaranteed sterile. Touching a sterile instrument to that edge contaminates the instrument.
Option A is correct as long as the surface is clean and dry. Option B is standard procedure. Option D is
correct as pouring from a height of 6 inches maintains sterility.
5. A nurse is caring for a patient with a surgical wound that is infected with methicillin-resistant
Staphylococcus aureus (MRSA). The nurse needs to change the wound dressing. Which of the
following infection control measures is most appropriate?
A. Wear clean gloves and a gown, perform hand hygiene after glove removal
B. Wear sterile gloves, a gown, and a face shield, and dispose of dressings in regular waste
C. Wear clean gloves, a gown, and a mask, and dispose of dressings in biohazard waste
D. Wear sterile gloves and a gown, and perform hand hygiene before gloving
Answer: C
Rationale: For MRSA-infected wounds, contact and droplet precautions are indicated. Clean gloves and
gown protect the nurse; mask prevents droplet transmission during dressing changes. Dressing disposal
in biohazard waste prevents environmental contamination. Option A lacks mask and proper waste
disposal. Option B's face shield is not necessary for standard precautions, and sterile gloves are not
required for clean technique. Option D omits mask and proper disposal.
6. A nurse is preparing to administer a saline lock flush through a peripheral intravenous catheter.
The catheter was inserted 72 hours ago and the site appears clean and dry. Which of the following
actions is consistent with clean technique?
A. Clean the injection port with an alcohol pad for 15 seconds, allow to dry, then inject using a sterile syringe
B. Wipe the injection port with a dry cotton ball, then inject using a clean syringe
C. Use a new needleless connector without cleaning the port, then flush using a sterile syringe
D. Clean the port with a chlorhexidine swab for 5 seconds, then inject immediately using a sterile syringe
Answer: A
Rationale: Cleaning the injection port with alcohol for 15 seconds and allowing it to dry reduces
microbial contamination. Using a sterile syringe maintains asepsis. Option B uses a dry cotton ball (no
disinfection) and a clean syringe (not sterile). Option C omits port disinfection, which is essential.
Page 2
,Option D's 5-second scrub and immediate injection do not allow adequate contact time or drying.
7. A nurse is teaching a patient about clean technique for self-catheterization at home. Which of
the following patient statements indicates a correct understanding?
A. I will boil the catheter for 10 minutes before each use
B. I will wash my hands with soap and water for 20 seconds before inserting the catheter
C. I will use the same catheter for one week, cleaning it with alcohol between uses
D. I will lubricate the catheter with petroleum jelly to make insertion easier
Answer: B
Rationale: In clean self-catheterization, hand hygiene with soap and water for 20 seconds is
recommended. Option A is unnecessary and may damage the catheter; clean technique does not require
sterilization. Option C is incorrect because catheters should be single-use or cleaned according to
manufacturer instructions; alcohol may not adequately disinfect and can degrade materials. Option D is
incorrect because petroleum jelly is not sterile and can cause infection; water-soluble lubricant is
preferred.
8. A nurse is preparing to administer an intravenous medication through a peripheral line. The
medication is compatible with normal saline. The nurse notes that the tubing has been in use for 96
hours. Which of the following actions is most appropriate?
A. Replace the tubing and administer the medication through the new tubing
B. Flush the existing tubing with normal saline and administer the medication
C. Replace the entire IV set including the catheter and tubing
D. Administer the medication through the existing tubing, then replace the tubing
Answer: A
Rationale: IV tubing should be replaced every 96 hours per CDC guidelines to reduce infection risk.
Administering medication through new tubing maintains aseptic technique. Option B uses contaminated
tubing that may harbor biofilm. Option C is unnecessary as catheter replacement is not indicated unless
signs of infection or phlebitis are present. Option D administers through contaminated tubing first,
increasing infection risk.
9. A nurse is setting up a sterile field for a bedside procedure. The nurse opens the sterile kit and
notices that the chemical indicator strip on the outside of the kit is not the expected color. Which of
the following actions should the nurse take?
A. Use the kit if the items inside appear clean and intact
B. Discard the kit and obtain a new one
C. Remove the indicator strip and proceed with the procedure
D. Check the expiration date; if valid, use the kit
Answer: B
Rationale: The chemical indicator strip confirms that the sterilization process was completed. An
unexpected color indicates that sterilization may not have been achieved, so the kit should not be used.
Option A is unsafe because appearance does not guarantee sterility. Option C is incorrect because
ignoring the indicator compromises patient safety. Option D is insufficient because a valid expiration
date does not ensure sterilization if the indicator failed.
Page 3
, 10. A nurse is caring for a patient with a tracheostomy who requires suctioning. Which of the
following techniques is most appropriate for maintaining clean technique during suctioning?
A. Use a sterile suction catheter and sterile gloves for each suctioning episode
B. Use a clean suction catheter and clean gloves for each suctioning episode
C. Use a sterile suction catheter and clean gloves for each suctioning episode
D. Use the same suction catheter for 24 hours, rinsing with sterile water between uses
Answer: A
Rationale: Tracheal suctioning requires sterile technique because the lower respiratory tract is normally
sterile. Using a sterile catheter and sterile gloves minimizes infection risk. Option B uses clean
equipment, which can introduce pathogens. Option C's clean gloves do not provide adequate barrier
protection. Option D reuses a catheter, which is unsafe and increases infection risk even with rinsing.
11. A research team is designing a cleanroom for nanofabrication of quantum dots. The process
requires controlling both particle and molecular contamination. Which combination of cleanroom
classification and airflow design is most appropriate to achieve ISO Class 3 conditions with
minimal turbulence and maximum contaminant removal efficiency?
A. ISO Class 3 with unidirectional vertical airflow at 0.45 m/s, HEPA filters at ceiling, raised floor return
B. ISO Class 3 with unidirectional horizontal airflow at 0.5 m/s, HEPA filters on one wall, return on opposite
wall
C. ISO Class 4 with turbulent airflow at 20 air changes per hour, ULPA filters, ceiling return grilles
D. ISO Class 3 with unidirectional vertical airflow at 0.3 m/s, ULPA filters, low wall returns
Answer: A
Rationale: ISO Class 3 requires extremely low particle counts and is best achieved with unidirectional
vertical airflow at 0.45 m/s (the standard for ISO Class 5 and better) with HEPA/ULPA filters and raised
floor returns to minimize turbulence. Horizontal airflow is less effective for cleanliness classes better
than ISO 5. Lower airflow (0.3 m/s) may not maintain unidirectional flow. ISO Class 4 is less stringent
and turbulent flow is insufficient.
12. In a cleanroom used for aseptic filling of biopharmaceuticals, a technician notices that the
particle count at the critical work zone exceeds the ISO Class 5 limit during dynamic conditions.
The investigation reveals that the HEPA filter integrity test (DOP test) is satisfactory, but the room
pressure differential to the adjacent corridor has dropped from +15 Pa to +8 Pa. Which of the
following is the most likely cause of the elevated particle counts?
A. Recirculation of particles from the return air path due to inadequate HEPA filter sealing
B. Increased particle generation from the technician's gowning material due to static discharge
C. Ingress of contaminated air from the corridor through leaks in the room envelope
D. Saturation of the HEPA filters causing bypass flow around the filter media
Answer: C
Rationale: A reduced positive pressure differential (from +15 Pa to +8 Pa) compromises the ability to
prevent influx of less clean air from the corridor. Even with intact HEPA filters, lower pressure allows
contaminated air to enter through gaps around doors, walls, or utility penetrations. Filter sealing issues
would not be detected by a passing DOP test. Static discharge and filter saturation are less likely given
the specific change in pressure differential.
Page 4
Questions And Correct Detailed Answers| Already
Graded A+
1. A nurse is preparing to insert an indwelling urinary catheter using clean technique. The patient
has a history of recurrent urinary tract infections. Which of the following actions is most critical
for reducing infection risk during this procedure?
A. Using a sterile catheter and sterile lubricant, but clean gloves for insertion
B. Applying an antiseptic solution to the perineum using a clean cotton ball
C. Opening the catheter kit and touching the inner surface of the sterile drape with clean hands
D. Performing hand hygiene, then donning sterile gloves before handling the catheter
Answer: D
Rationale: For indwelling catheter insertion, sterile technique is required to prevent introducing
pathogens into the bladder. Hand hygiene and sterile gloves are essential. Option A is incorrect because
clean gloves do not provide adequate barrier protection. Option B is incorrect because clean cotton
balls are not sterile and may introduce microbes. Option C is incorrect because touching the sterile
drape with clean hands contaminates the field.
2. A nurse is changing a surgical wound dressing using clean technique. The wound is healing by
secondary intention and has moderate serosanguinous drainage. Which of the following actions
demonstrates correct application of clean technique?
A. Using sterile gloves and a sterile dressing, but cleaning the wound with tap water
B. Using clean gloves and a clean dressing, and cleaning the wound with sterile saline
C. Using sterile gloves and clean dressing, and cleaning the wound with hydrogen peroxide
D. Using clean gloves and sterile dressing, and cleaning the wound with sterile saline
Answer: D
Rationale: For clean technique wound care, clean gloves protect the nurse, while sterile dressing and
sterile saline prevent contamination of the healing wound. Option A is incorrect because tap water is not
sterile. Option B uses clean dressing, which is not sterile and may introduce pathogens. Option C uses
hydrogen peroxide, which can damage tissue and is not recommended for routine wound cleaning.
3. A nurse is preparing to administer a blood transfusion. The patient has a central venous
catheter. Which of the following best describes the required aseptic technique for connecting the
blood tubing to the catheter hub?
A. Clean the hub with an alcohol swab for 5 seconds and allow to dry, then connect using clean gloves
B. Scrub the hub with a 70% alcohol pad for 15 seconds and allow to dry, then connect using sterile gloves
C. Wipe the hub with a chlorhexidine wipe for 10 seconds, then connect immediately using clean gloves
D. Use a new sterile cap on the hub without additional cleaning, then connect using sterile gloves
Page 1
,Answer: B
Rationale: Blood transfusions require sterile technique due to high infection risk. Scrubbing the hub for
15 seconds with alcohol and allowing it to dry ensures disinfection. Sterile gloves prevent
contamination. Option A's shorter scrub and clean gloves are insufficient. Option C's immediate
connection after chlorhexidine does not allow drying, reducing efficacy. Option D omits hub
disinfection, which is necessary even with a new cap.
4. A nurse is setting up a sterile field for a lumbar puncture. Which of the following actions would
most likely compromise the sterility of the field?
A. Placing the sterile drape on a clean, dry surface
B. Opening the outer wrapper of a sterile package before opening the inner wrapper
C. Allowing a sterile instrument to touch the edge of the sterile drape
D. Pouring sterile solution into a sterile basin from a height of 6 inches
Answer: C
Rationale: The edge of a sterile drape (typically 1 inch border) is considered contaminated because it
cannot be guaranteed sterile. Touching a sterile instrument to that edge contaminates the instrument.
Option A is correct as long as the surface is clean and dry. Option B is standard procedure. Option D is
correct as pouring from a height of 6 inches maintains sterility.
5. A nurse is caring for a patient with a surgical wound that is infected with methicillin-resistant
Staphylococcus aureus (MRSA). The nurse needs to change the wound dressing. Which of the
following infection control measures is most appropriate?
A. Wear clean gloves and a gown, perform hand hygiene after glove removal
B. Wear sterile gloves, a gown, and a face shield, and dispose of dressings in regular waste
C. Wear clean gloves, a gown, and a mask, and dispose of dressings in biohazard waste
D. Wear sterile gloves and a gown, and perform hand hygiene before gloving
Answer: C
Rationale: For MRSA-infected wounds, contact and droplet precautions are indicated. Clean gloves and
gown protect the nurse; mask prevents droplet transmission during dressing changes. Dressing disposal
in biohazard waste prevents environmental contamination. Option A lacks mask and proper waste
disposal. Option B's face shield is not necessary for standard precautions, and sterile gloves are not
required for clean technique. Option D omits mask and proper disposal.
6. A nurse is preparing to administer a saline lock flush through a peripheral intravenous catheter.
The catheter was inserted 72 hours ago and the site appears clean and dry. Which of the following
actions is consistent with clean technique?
A. Clean the injection port with an alcohol pad for 15 seconds, allow to dry, then inject using a sterile syringe
B. Wipe the injection port with a dry cotton ball, then inject using a clean syringe
C. Use a new needleless connector without cleaning the port, then flush using a sterile syringe
D. Clean the port with a chlorhexidine swab for 5 seconds, then inject immediately using a sterile syringe
Answer: A
Rationale: Cleaning the injection port with alcohol for 15 seconds and allowing it to dry reduces
microbial contamination. Using a sterile syringe maintains asepsis. Option B uses a dry cotton ball (no
disinfection) and a clean syringe (not sterile). Option C omits port disinfection, which is essential.
Page 2
,Option D's 5-second scrub and immediate injection do not allow adequate contact time or drying.
7. A nurse is teaching a patient about clean technique for self-catheterization at home. Which of
the following patient statements indicates a correct understanding?
A. I will boil the catheter for 10 minutes before each use
B. I will wash my hands with soap and water for 20 seconds before inserting the catheter
C. I will use the same catheter for one week, cleaning it with alcohol between uses
D. I will lubricate the catheter with petroleum jelly to make insertion easier
Answer: B
Rationale: In clean self-catheterization, hand hygiene with soap and water for 20 seconds is
recommended. Option A is unnecessary and may damage the catheter; clean technique does not require
sterilization. Option C is incorrect because catheters should be single-use or cleaned according to
manufacturer instructions; alcohol may not adequately disinfect and can degrade materials. Option D is
incorrect because petroleum jelly is not sterile and can cause infection; water-soluble lubricant is
preferred.
8. A nurse is preparing to administer an intravenous medication through a peripheral line. The
medication is compatible with normal saline. The nurse notes that the tubing has been in use for 96
hours. Which of the following actions is most appropriate?
A. Replace the tubing and administer the medication through the new tubing
B. Flush the existing tubing with normal saline and administer the medication
C. Replace the entire IV set including the catheter and tubing
D. Administer the medication through the existing tubing, then replace the tubing
Answer: A
Rationale: IV tubing should be replaced every 96 hours per CDC guidelines to reduce infection risk.
Administering medication through new tubing maintains aseptic technique. Option B uses contaminated
tubing that may harbor biofilm. Option C is unnecessary as catheter replacement is not indicated unless
signs of infection or phlebitis are present. Option D administers through contaminated tubing first,
increasing infection risk.
9. A nurse is setting up a sterile field for a bedside procedure. The nurse opens the sterile kit and
notices that the chemical indicator strip on the outside of the kit is not the expected color. Which of
the following actions should the nurse take?
A. Use the kit if the items inside appear clean and intact
B. Discard the kit and obtain a new one
C. Remove the indicator strip and proceed with the procedure
D. Check the expiration date; if valid, use the kit
Answer: B
Rationale: The chemical indicator strip confirms that the sterilization process was completed. An
unexpected color indicates that sterilization may not have been achieved, so the kit should not be used.
Option A is unsafe because appearance does not guarantee sterility. Option C is incorrect because
ignoring the indicator compromises patient safety. Option D is insufficient because a valid expiration
date does not ensure sterilization if the indicator failed.
Page 3
, 10. A nurse is caring for a patient with a tracheostomy who requires suctioning. Which of the
following techniques is most appropriate for maintaining clean technique during suctioning?
A. Use a sterile suction catheter and sterile gloves for each suctioning episode
B. Use a clean suction catheter and clean gloves for each suctioning episode
C. Use a sterile suction catheter and clean gloves for each suctioning episode
D. Use the same suction catheter for 24 hours, rinsing with sterile water between uses
Answer: A
Rationale: Tracheal suctioning requires sterile technique because the lower respiratory tract is normally
sterile. Using a sterile catheter and sterile gloves minimizes infection risk. Option B uses clean
equipment, which can introduce pathogens. Option C's clean gloves do not provide adequate barrier
protection. Option D reuses a catheter, which is unsafe and increases infection risk even with rinsing.
11. A research team is designing a cleanroom for nanofabrication of quantum dots. The process
requires controlling both particle and molecular contamination. Which combination of cleanroom
classification and airflow design is most appropriate to achieve ISO Class 3 conditions with
minimal turbulence and maximum contaminant removal efficiency?
A. ISO Class 3 with unidirectional vertical airflow at 0.45 m/s, HEPA filters at ceiling, raised floor return
B. ISO Class 3 with unidirectional horizontal airflow at 0.5 m/s, HEPA filters on one wall, return on opposite
wall
C. ISO Class 4 with turbulent airflow at 20 air changes per hour, ULPA filters, ceiling return grilles
D. ISO Class 3 with unidirectional vertical airflow at 0.3 m/s, ULPA filters, low wall returns
Answer: A
Rationale: ISO Class 3 requires extremely low particle counts and is best achieved with unidirectional
vertical airflow at 0.45 m/s (the standard for ISO Class 5 and better) with HEPA/ULPA filters and raised
floor returns to minimize turbulence. Horizontal airflow is less effective for cleanliness classes better
than ISO 5. Lower airflow (0.3 m/s) may not maintain unidirectional flow. ISO Class 4 is less stringent
and turbulent flow is insufficient.
12. In a cleanroom used for aseptic filling of biopharmaceuticals, a technician notices that the
particle count at the critical work zone exceeds the ISO Class 5 limit during dynamic conditions.
The investigation reveals that the HEPA filter integrity test (DOP test) is satisfactory, but the room
pressure differential to the adjacent corridor has dropped from +15 Pa to +8 Pa. Which of the
following is the most likely cause of the elevated particle counts?
A. Recirculation of particles from the return air path due to inadequate HEPA filter sealing
B. Increased particle generation from the technician's gowning material due to static discharge
C. Ingress of contaminated air from the corridor through leaks in the room envelope
D. Saturation of the HEPA filters causing bypass flow around the filter media
Answer: C
Rationale: A reduced positive pressure differential (from +15 Pa to +8 Pa) compromises the ability to
prevent influx of less clean air from the corridor. Even with intact HEPA filters, lower pressure allows
contaminated air to enter through gaps around doors, walls, or utility penetrations. Filter sealing issues
would not be detected by a passing DOP test. Static discharge and filter saturation are less likely given
the specific change in pressure differential.
Page 4
