BLS (Basic Life Support) practice exam Questions
and Correct Answers (Verified Answers) with
Rationales 2025
1. What is the first step in the BLS assessment for an unresponsive
adult?
Check for responsiveness
Assessing responsiveness ensures the need for further help and
identifies cardiac arrest early.
2. What is the recommended compression rate for adult CPR?
100-120 compressions per minute
This rate ensures optimal blood flow during chest compressions.
3. What is the compression depth for an adult victim?
At least 2 inches (5 cm)
This depth is needed to generate adequate circulation without
causing injury.
4. How often should rescue breaths be given during CPR with an
advanced airway?
1 breath every 6 seconds
, Ventilations should not interrupt compressions in advanced airway
scenarios.
5. How do you open the airway of an unresponsive victim without
suspected trauma?
Head tilt–chin lift
This is the preferred method unless spinal injury is suspected.
6. What is the correct compression-to-ventilation ratio for a single
rescuer in adult CPR?
30:2
This ratio provides a balance of compressions and breaths.
7. What is the compression-to-ventilation ratio for 2-rescuer child
CPR?
15:2
Increased ventilation is needed in children due to higher
respiratory demands.
8. What is the first action you should take if you witness a sudden
collapse of an adult?
Activate the emergency response system
Getting help early is critical in sudden cardiac arrest.
,9. What is the correct hand placement for adult chest compressions?
Lower half of the sternum
This location targets the heart most effectively.
10. How long should you check for a pulse in an unresponsive
victim?
No more than 10 seconds
Delaying CPR reduces survival chances.
11. What is the best way to ensure effective CPR?
Allow chest to fully recoil between compressions
Full recoil allows the heart to refill, improving blood flow.
12. What should be done immediately after a shock is delivered
by an AED?
Resume CPR
Continue compressions immediately to maintain circulation.
13. Which pulse is checked in an unresponsive adult?
Carotid pulse
This pulse is most accessible and reliable in adults.
14. What is the compression depth for an infant?
About 1.5 inches (4 cm)
Smaller depth matches the size of an infant's chest.
, 15. When is it appropriate to use an AED on a child under 8
years old?
As soon as it is available
Early defibrillation increases survival chances.
16. What should you do if you see a child collapse and are alone
without a phone?
Begin CPR for 2 minutes, then activate EMS
Immediate CPR is essential before leaving the child.
17. What is the preferred method of providing breaths in BLS?
Using a barrier device or bag-mask
This protects both rescuer and victim and ensures effective
ventilation.
18. What should be done when a person has a pulse but is not
breathing?
Give rescue breaths only
Compressions are unnecessary if there is a pulse.
19. What is the ventilation rate for rescue breathing in a child
with a pulse?
1 breath every 3–5 seconds
This rate provides adequate oxygen without hyperventilation.
and Correct Answers (Verified Answers) with
Rationales 2025
1. What is the first step in the BLS assessment for an unresponsive
adult?
Check for responsiveness
Assessing responsiveness ensures the need for further help and
identifies cardiac arrest early.
2. What is the recommended compression rate for adult CPR?
100-120 compressions per minute
This rate ensures optimal blood flow during chest compressions.
3. What is the compression depth for an adult victim?
At least 2 inches (5 cm)
This depth is needed to generate adequate circulation without
causing injury.
4. How often should rescue breaths be given during CPR with an
advanced airway?
1 breath every 6 seconds
, Ventilations should not interrupt compressions in advanced airway
scenarios.
5. How do you open the airway of an unresponsive victim without
suspected trauma?
Head tilt–chin lift
This is the preferred method unless spinal injury is suspected.
6. What is the correct compression-to-ventilation ratio for a single
rescuer in adult CPR?
30:2
This ratio provides a balance of compressions and breaths.
7. What is the compression-to-ventilation ratio for 2-rescuer child
CPR?
15:2
Increased ventilation is needed in children due to higher
respiratory demands.
8. What is the first action you should take if you witness a sudden
collapse of an adult?
Activate the emergency response system
Getting help early is critical in sudden cardiac arrest.
,9. What is the correct hand placement for adult chest compressions?
Lower half of the sternum
This location targets the heart most effectively.
10. How long should you check for a pulse in an unresponsive
victim?
No more than 10 seconds
Delaying CPR reduces survival chances.
11. What is the best way to ensure effective CPR?
Allow chest to fully recoil between compressions
Full recoil allows the heart to refill, improving blood flow.
12. What should be done immediately after a shock is delivered
by an AED?
Resume CPR
Continue compressions immediately to maintain circulation.
13. Which pulse is checked in an unresponsive adult?
Carotid pulse
This pulse is most accessible and reliable in adults.
14. What is the compression depth for an infant?
About 1.5 inches (4 cm)
Smaller depth matches the size of an infant's chest.
, 15. When is it appropriate to use an AED on a child under 8
years old?
As soon as it is available
Early defibrillation increases survival chances.
16. What should you do if you see a child collapse and are alone
without a phone?
Begin CPR for 2 minutes, then activate EMS
Immediate CPR is essential before leaving the child.
17. What is the preferred method of providing breaths in BLS?
Using a barrier device or bag-mask
This protects both rescuer and victim and ensures effective
ventilation.
18. What should be done when a person has a pulse but is not
breathing?
Give rescue breaths only
Compressions are unnecessary if there is a pulse.
19. What is the ventilation rate for rescue breathing in a child
with a pulse?
1 breath every 3–5 seconds
This rate provides adequate oxygen without hyperventilation.
