NHA Certified EKG Technician (CET) Exam –
Complete Practice Questions & Rationales 2026
Question 1
An EKG technician is measuring the intervals on an EKG tracing. Which of
the following would indicate a first-degree AV block?
A. PR interval of 0.16 seconds
B. PR interval of 0.28 seconds
C. QRS duration of 0.12 seconds
D. QT interval of 0.40 seconds
*Correct Answer: B. PR interval of 0.28 seconds. *
Rationale: First-degree AV block is characterized by a PR interval greater
than 0.20 seconds (one large box). A PR interval of 0.28 seconds is prolonged
and indicates delayed conduction through the AV node .
Question 2
Which of the following rhythms is characterized by upright P waves, narrow
QRS complexes, and a ventricular rate between 60 and 100/min?
A. Sinus bradycardia
B. Normal sinus rhythm
C. Junctional rhythm
D. Atrial fibrillation
*Correct Answer: B. Normal sinus rhythm. *
Rationale: Normal sinus rhythm is defined by a regular rhythm with upright P
waves preceding each QRS complex, a PR interval of 0.12–0.20 seconds, and
a ventricular rate of 60–100 bpm .
,Question 3
An EKG technician notes periods of sinus arrest on a patient's EKG tracing.
Which of the following is the most appropriate action?
A. Document the finding and continue monitoring
B. Notify the provider immediately
C. Administer atropine
D. Repeat the EKG
*Correct Answer: B. Notify the provider immediately. *
Rationale: Sinus arrest is a pause in the sinus node activity that can lead to
significant bradycardia or asystole. The provider should be notified
immediately for further evaluation .
Question 4
An EKG technician is preparing a patient for a standard 12-lead EKG. Which
of the following actions should the technician take first?
A. Cleanse the skin with alcohol
B. Have the patient remove any jewelry
C. Apply the electrodes to the patient's chest
D. Attach the lead wires to the electrodes
*Correct Answer: B. Have the patient remove any jewelry. *
Rationale: Patient safety is the priority. Jewelry can interfere with lead
placement and pose a safety risk. The technician should have the patient
remove any jewelry before beginning the procedure .
,Question 5
While performing a standard 12-lead EKG, an EKG technician notices that
none of the leads are giving a reading. Which electrode should the
technician check first?
A. Right arm
B. Left arm
C. Left leg
D. Right leg
*Correct Answer: D. Right leg. *
Rationale: The right leg electrode serves as the ground for the EKG machine.
If none of the leads are producing a reading, the ground electrode is the most
likely point of failure .
Question 6
A patient loses consciousness, and the EKG tracing reveals ventricular
fibrillation. Which of the following should the EKG technician do first?
A. Document the event and observe the patient closely
B. Check the patient's blood pressure and administer oxygen
C. Call for help and begin CPR
D. Prepare the defibrillator
*Correct Answer: C. Call for help and begin CPR. *
Rationale: Ventricular fibrillation is a life-threatening arrhythmia. The first
action is to call for help and begin CPR immediately, followed by
defibrillation as soon as possible .
, Question 7
Which of the following EKG machine functions should an EKG technician
use to control and regulate the height of EKG waveforms on the tracing?
A. Speed
B. Gain
C. Filter
D. Calibration
*Correct Answer: B. Gain. *
Rationale: The gain control adjusts the amplitude (height) of the EKG
waveforms. The standard setting is 10 mm/mV .
Question 8
An EKG technician is preparing a patient for a scheduled standard 12-lead
EKG. Which of the following actions should the technician take to prepare
the electrode placement sites?
A. Apply moisturizing lotion to the skin
B. Use an alcohol pad to cleanse the electrode placement sites
C. Shave the skin with a razor
D. Apply electrode gel to the entire chest
*Correct Answer: B. Use an alcohol pad to cleanse the electrode
placement sites. *
Rationale: Alcohol pads remove skin oils and debris, improving electrode
adhesion and reducing skin impedance, which leads to better signal quality .
Question 9
An EKG technician is caring for a patient who is experiencing heart
Complete Practice Questions & Rationales 2026
Question 1
An EKG technician is measuring the intervals on an EKG tracing. Which of
the following would indicate a first-degree AV block?
A. PR interval of 0.16 seconds
B. PR interval of 0.28 seconds
C. QRS duration of 0.12 seconds
D. QT interval of 0.40 seconds
*Correct Answer: B. PR interval of 0.28 seconds. *
Rationale: First-degree AV block is characterized by a PR interval greater
than 0.20 seconds (one large box). A PR interval of 0.28 seconds is prolonged
and indicates delayed conduction through the AV node .
Question 2
Which of the following rhythms is characterized by upright P waves, narrow
QRS complexes, and a ventricular rate between 60 and 100/min?
A. Sinus bradycardia
B. Normal sinus rhythm
C. Junctional rhythm
D. Atrial fibrillation
*Correct Answer: B. Normal sinus rhythm. *
Rationale: Normal sinus rhythm is defined by a regular rhythm with upright P
waves preceding each QRS complex, a PR interval of 0.12–0.20 seconds, and
a ventricular rate of 60–100 bpm .
,Question 3
An EKG technician notes periods of sinus arrest on a patient's EKG tracing.
Which of the following is the most appropriate action?
A. Document the finding and continue monitoring
B. Notify the provider immediately
C. Administer atropine
D. Repeat the EKG
*Correct Answer: B. Notify the provider immediately. *
Rationale: Sinus arrest is a pause in the sinus node activity that can lead to
significant bradycardia or asystole. The provider should be notified
immediately for further evaluation .
Question 4
An EKG technician is preparing a patient for a standard 12-lead EKG. Which
of the following actions should the technician take first?
A. Cleanse the skin with alcohol
B. Have the patient remove any jewelry
C. Apply the electrodes to the patient's chest
D. Attach the lead wires to the electrodes
*Correct Answer: B. Have the patient remove any jewelry. *
Rationale: Patient safety is the priority. Jewelry can interfere with lead
placement and pose a safety risk. The technician should have the patient
remove any jewelry before beginning the procedure .
,Question 5
While performing a standard 12-lead EKG, an EKG technician notices that
none of the leads are giving a reading. Which electrode should the
technician check first?
A. Right arm
B. Left arm
C. Left leg
D. Right leg
*Correct Answer: D. Right leg. *
Rationale: The right leg electrode serves as the ground for the EKG machine.
If none of the leads are producing a reading, the ground electrode is the most
likely point of failure .
Question 6
A patient loses consciousness, and the EKG tracing reveals ventricular
fibrillation. Which of the following should the EKG technician do first?
A. Document the event and observe the patient closely
B. Check the patient's blood pressure and administer oxygen
C. Call for help and begin CPR
D. Prepare the defibrillator
*Correct Answer: C. Call for help and begin CPR. *
Rationale: Ventricular fibrillation is a life-threatening arrhythmia. The first
action is to call for help and begin CPR immediately, followed by
defibrillation as soon as possible .
, Question 7
Which of the following EKG machine functions should an EKG technician
use to control and regulate the height of EKG waveforms on the tracing?
A. Speed
B. Gain
C. Filter
D. Calibration
*Correct Answer: B. Gain. *
Rationale: The gain control adjusts the amplitude (height) of the EKG
waveforms. The standard setting is 10 mm/mV .
Question 8
An EKG technician is preparing a patient for a scheduled standard 12-lead
EKG. Which of the following actions should the technician take to prepare
the electrode placement sites?
A. Apply moisturizing lotion to the skin
B. Use an alcohol pad to cleanse the electrode placement sites
C. Shave the skin with a razor
D. Apply electrode gel to the entire chest
*Correct Answer: B. Use an alcohol pad to cleanse the electrode
placement sites. *
Rationale: Alcohol pads remove skin oils and debris, improving electrode
adhesion and reducing skin impedance, which leads to better signal quality .
Question 9
An EKG technician is caring for a patient who is experiencing heart
