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CST Certification Exam Actual
Exam 2026/2027 | Questions with
Verified Answers | 100% Correct |
Pass Guaranteed
Subdomain: Aseptic Technique & Sterile Field
Q1: While opening a sterile back-table pack, the surgical technologist notes an
unidentifiable 1-inch tear in the wrapper’s paper layer; the plastic liner beneath
is intact. What is the MOST appropriate action?
A. Proceed with setup —the plastic liner maintains the barrier.
B. Use the pack for a low-infection-risk procedure.
C. Discard the entire pack and obtain a new one.
D. Cover the tear with a sterile impervious drape before proceeding.
Correct Answer: C
Verified Solution & Rationale: AORN Guideline for Sterile Technique states
any breach in package wrapper integrity, regardless of inner-liner status, renders
contents non-sterile and requires pack rejection.
Q2: The sterile field has been set for 30 min when a non-sterile circulating nurse
reaches over it to plug in a cord; the sleeve passes 6 in above the drapes. What
must the technologist do?
A. Continue—no contact occurred.
B. Replace only items directly beneath the path.
C. Strike the entire field and set up anew.
D. Apply a sterile drape over the “contaminated” area.
Correct Answer: C
Verified Solution & Rationale: AORN defines the sterile field perimeter as 12
in of vertical unsterile space; any intrusion within that space necessitates
complete field breakdown and re-prep.
Q3: Which hand scrub agent provides the highest persistent antimicrobial
residual per AST Core Curriculum 2026?
A. 7.5 % povidone-iodine scrub
B. 2 % chlorhexidine gluconate with 70 % isopropyl alcohol
C. 3 % parachlorometaxylenol foam
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D. Plain 70 % isopropyl alcohol alone
Correct Answer: B
Verified Solution & Rationale: Chlorhexidine gluconate/alcohol combines rapid
kill with up to 6 h residual activity, exceeding other listed agents per AST
recommendations.
Q4: During gowning, the cuff of the sterile gown flips back 1 cm, exposing the
wrist skin. The technologist’s next action is:
A. Ask a team member to pull the cuff over the wrist.
B. Remove and regown using closed-glove technique.
C. Don sterile gloves using open-glove method to cover.
D. Apply a sterile sleeve over the exposed area.
Correct Answer: B
Verified Solution & Rationale: AORN sterile attire standards require immediate
regowning when skin is exposed because wrist skin is non-sterile and cannot be
covered secondarily.
Q5: The back table is covered with a sterile drape. How far may the
technologist reach over the table without compromising sterility?
A. 2 in
B. 6 in
C. 12 in
D. 18 in
Correct Answer: A
Verified Solution & Rationale: AORN defines the 2-in border at table edges as
the only zone a sterile-gowned person may lean over; beyond this, sterile items
are considered contaminated.
Q6: A package labeled “STERILE unless opened or damaged” is found with
water stains on the outer wrap but is sealed. What action is required?
A. Use immediately—seal intact.
B. Dry with sterile towel then use.
A. Send to sterile processing for re-sterilization.
D. Discard; moisture breaches sterility.
Correct Answer: D
Verified Solution & Rationale: AORN moisture is a sterility event because
capillary action can draw microorganisms through wrap; stained packs are non-
sterile.
Q7: The technologist sets up a back table at 07:00 for a 09:00 case; no sterile
items are opened. At 08:45 the circulator wants to start the case. What is
correct?
A. Cover table with sterile drape until patient enters.
B. Remove outer drape and continue.
C. Strike and reset entire field.
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D. Wipe surfaces with sterile saline.
Correct Answer: C
Verified Solution & Rationale: AORN limits sterile field longevity to 1 h from
completion of setup when case has not started; beyond that, strike and reset.
Q8: Which item is considered sterile once opened onto the field?
A. Inner plastic pouch of a double-pouched catheter
B. Outer dust cover of a light-handle sleeve
C. Cardboard lid of suture box
D. Paper instruction insert
Correct Answer: A
Verified Solution & Rationale: Only the inner peel pouch of a double-pouched
sterile item is presented to the field; outer surfaces are unsterile.
Q9: When flipping a sterile item onto the field, the technologist touches the
inner peel pouch edge to the drape. What is required?
A. Continue—inner edge is sterile.
B. Replace the drape touched.
C. Discard the item.
D. Wipe touched area with alcohol.
Correct Answer: B
Verified Solution & Rationale: AORN states the inner peel pouch edge is non -
sterile; any contact with drape necessitates drape replacement.
Q10: The circulator opens a basin set and drops it 12 in onto the field; the basin
rim lands on the drape. What is correct?
A. Accept basin—gravity drop is allowed.
B. Replace only the drape beneath rim.
C. Remove basin; field remains sterile.
D. Strike entire field.
Correct Answer: D
Verified Solution & Rationale: A gravity drop >6 in can generate airflow
turbulence and is considered contaminated; entire field must be re-set.
Q11: Which portion of a sterile gown is considered non-sterile once donned?
A. Sleeves from 2 in above elbow to cuff
B. Gown front from nipple to waist
C. Axillary regions due to moisture
D. Neckline ties when secured in front
Correct Answer: C
Verified Solution & Rationale: AORN designates axillary areas as potentially
contaminated by perspiration regardless of gown material.
Q12: During draping, the technologist contaminates a small corner of the
laparotomy drape. Best action?
A. Discard drape and replace.
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B. Cover with sterile towel.
C. Rotate drape 180°.
D. Use fenestrated drape over it.
Correct Answer: A
Verified Solution & Rationale: Any portion of a drape contacting unsterile
items is contaminated; replacement is mandatory—covering is prohibited.
Q13: The sterile glove package is torn on opening but gloves remain inside.
What is correct?
A. Use gloves—package integrity secondary.
B. Inspect gloves then use.
C. Discard package and gloves.
D. Re-sterilize gloves.
Correct Answer: C
Verified Solution & Rationale: Torn glove packaging breaches sterility; gloves
are non-sterile and cannot be field-sterilized.
Q14: Which action best maintains sterile field when passing a sharp?
A. Hand off sharp in neutral zone.
B. Pass directly blade-up.
C. Place on Mayo stand edge.
D. Use magnetic pad on back table.
Correct Answer: A
Verified Solution & Rationale: AORN sharps safety and sterile field guidelines
endorse a neutral zone to prevent glove perforation and maintain sterility.
Q15: A sterile table is bumped by anesthesia cart; one instrument falls to floor.
Next step?
A. Retrieve, clean, and replace.
B. Replace instrument only.
C. Remove instrument; field remains sterile.
D. Re-drape entire table.
Correct Answer: B
Verified Solution & Rationale: Only the fallen instrument is contaminated;
removal and replacement preserves field without full re-draping.
Q16: When opening a bottle of sterile saline onto the field, the technologist
should:
A. Pour with label facing up, bottle 2 in above basin.
B. Touch lip of bottle to inside of basin.
C. Recap unused portion for later.
D. Hold bottle 6 in above field to prevent splash.
Correct Answer: D
Verified Solution & Rationale: AORN requires 6-in height to avoid droplet
backsplash onto sterile areas; recapping is prohibited.
CST Certification Exam Actual
Exam 2026/2027 | Questions with
Verified Answers | 100% Correct |
Pass Guaranteed
Subdomain: Aseptic Technique & Sterile Field
Q1: While opening a sterile back-table pack, the surgical technologist notes an
unidentifiable 1-inch tear in the wrapper’s paper layer; the plastic liner beneath
is intact. What is the MOST appropriate action?
A. Proceed with setup —the plastic liner maintains the barrier.
B. Use the pack for a low-infection-risk procedure.
C. Discard the entire pack and obtain a new one.
D. Cover the tear with a sterile impervious drape before proceeding.
Correct Answer: C
Verified Solution & Rationale: AORN Guideline for Sterile Technique states
any breach in package wrapper integrity, regardless of inner-liner status, renders
contents non-sterile and requires pack rejection.
Q2: The sterile field has been set for 30 min when a non-sterile circulating nurse
reaches over it to plug in a cord; the sleeve passes 6 in above the drapes. What
must the technologist do?
A. Continue—no contact occurred.
B. Replace only items directly beneath the path.
C. Strike the entire field and set up anew.
D. Apply a sterile drape over the “contaminated” area.
Correct Answer: C
Verified Solution & Rationale: AORN defines the sterile field perimeter as 12
in of vertical unsterile space; any intrusion within that space necessitates
complete field breakdown and re-prep.
Q3: Which hand scrub agent provides the highest persistent antimicrobial
residual per AST Core Curriculum 2026?
A. 7.5 % povidone-iodine scrub
B. 2 % chlorhexidine gluconate with 70 % isopropyl alcohol
C. 3 % parachlorometaxylenol foam
,2
D. Plain 70 % isopropyl alcohol alone
Correct Answer: B
Verified Solution & Rationale: Chlorhexidine gluconate/alcohol combines rapid
kill with up to 6 h residual activity, exceeding other listed agents per AST
recommendations.
Q4: During gowning, the cuff of the sterile gown flips back 1 cm, exposing the
wrist skin. The technologist’s next action is:
A. Ask a team member to pull the cuff over the wrist.
B. Remove and regown using closed-glove technique.
C. Don sterile gloves using open-glove method to cover.
D. Apply a sterile sleeve over the exposed area.
Correct Answer: B
Verified Solution & Rationale: AORN sterile attire standards require immediate
regowning when skin is exposed because wrist skin is non-sterile and cannot be
covered secondarily.
Q5: The back table is covered with a sterile drape. How far may the
technologist reach over the table without compromising sterility?
A. 2 in
B. 6 in
C. 12 in
D. 18 in
Correct Answer: A
Verified Solution & Rationale: AORN defines the 2-in border at table edges as
the only zone a sterile-gowned person may lean over; beyond this, sterile items
are considered contaminated.
Q6: A package labeled “STERILE unless opened or damaged” is found with
water stains on the outer wrap but is sealed. What action is required?
A. Use immediately—seal intact.
B. Dry with sterile towel then use.
A. Send to sterile processing for re-sterilization.
D. Discard; moisture breaches sterility.
Correct Answer: D
Verified Solution & Rationale: AORN moisture is a sterility event because
capillary action can draw microorganisms through wrap; stained packs are non-
sterile.
Q7: The technologist sets up a back table at 07:00 for a 09:00 case; no sterile
items are opened. At 08:45 the circulator wants to start the case. What is
correct?
A. Cover table with sterile drape until patient enters.
B. Remove outer drape and continue.
C. Strike and reset entire field.
,3
D. Wipe surfaces with sterile saline.
Correct Answer: C
Verified Solution & Rationale: AORN limits sterile field longevity to 1 h from
completion of setup when case has not started; beyond that, strike and reset.
Q8: Which item is considered sterile once opened onto the field?
A. Inner plastic pouch of a double-pouched catheter
B. Outer dust cover of a light-handle sleeve
C. Cardboard lid of suture box
D. Paper instruction insert
Correct Answer: A
Verified Solution & Rationale: Only the inner peel pouch of a double-pouched
sterile item is presented to the field; outer surfaces are unsterile.
Q9: When flipping a sterile item onto the field, the technologist touches the
inner peel pouch edge to the drape. What is required?
A. Continue—inner edge is sterile.
B. Replace the drape touched.
C. Discard the item.
D. Wipe touched area with alcohol.
Correct Answer: B
Verified Solution & Rationale: AORN states the inner peel pouch edge is non -
sterile; any contact with drape necessitates drape replacement.
Q10: The circulator opens a basin set and drops it 12 in onto the field; the basin
rim lands on the drape. What is correct?
A. Accept basin—gravity drop is allowed.
B. Replace only the drape beneath rim.
C. Remove basin; field remains sterile.
D. Strike entire field.
Correct Answer: D
Verified Solution & Rationale: A gravity drop >6 in can generate airflow
turbulence and is considered contaminated; entire field must be re-set.
Q11: Which portion of a sterile gown is considered non-sterile once donned?
A. Sleeves from 2 in above elbow to cuff
B. Gown front from nipple to waist
C. Axillary regions due to moisture
D. Neckline ties when secured in front
Correct Answer: C
Verified Solution & Rationale: AORN designates axillary areas as potentially
contaminated by perspiration regardless of gown material.
Q12: During draping, the technologist contaminates a small corner of the
laparotomy drape. Best action?
A. Discard drape and replace.
, 4
B. Cover with sterile towel.
C. Rotate drape 180°.
D. Use fenestrated drape over it.
Correct Answer: A
Verified Solution & Rationale: Any portion of a drape contacting unsterile
items is contaminated; replacement is mandatory—covering is prohibited.
Q13: The sterile glove package is torn on opening but gloves remain inside.
What is correct?
A. Use gloves—package integrity secondary.
B. Inspect gloves then use.
C. Discard package and gloves.
D. Re-sterilize gloves.
Correct Answer: C
Verified Solution & Rationale: Torn glove packaging breaches sterility; gloves
are non-sterile and cannot be field-sterilized.
Q14: Which action best maintains sterile field when passing a sharp?
A. Hand off sharp in neutral zone.
B. Pass directly blade-up.
C. Place on Mayo stand edge.
D. Use magnetic pad on back table.
Correct Answer: A
Verified Solution & Rationale: AORN sharps safety and sterile field guidelines
endorse a neutral zone to prevent glove perforation and maintain sterility.
Q15: A sterile table is bumped by anesthesia cart; one instrument falls to floor.
Next step?
A. Retrieve, clean, and replace.
B. Replace instrument only.
C. Remove instrument; field remains sterile.
D. Re-drape entire table.
Correct Answer: B
Verified Solution & Rationale: Only the fallen instrument is contaminated;
removal and replacement preserves field without full re-draping.
Q16: When opening a bottle of sterile saline onto the field, the technologist
should:
A. Pour with label facing up, bottle 2 in above basin.
B. Touch lip of bottle to inside of basin.
C. Recap unused portion for later.
D. Hold bottle 6 in above field to prevent splash.
Correct Answer: D
Verified Solution & Rationale: AORN requires 6-in height to avoid droplet
backsplash onto sterile areas; recapping is prohibited.
