EKG Technician (CET) Practice Test
Free EKG technician practice questions in English, Chinese, and Spanish — heart anatomy and conduction, 12-lead placement, rhythm identification, artifact troubleshooting, and patient safety, with an explanation for every answer.
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Practice questions based on the NHA Certified EKG Technician (CET) test plan, the standard 12-lead electrode positions defined by anatomical landmark, and durable cardiac electrophysiology. CET is a mark of the National Healthcareer Association; this site is not affiliated with or endorsed by NHA. An EKG technician records tracings and does not diagnose. Always follow your facility's policies, your state's scope of practice, and the direction of the ordering provider.
About the CET EKG technician exam
An EKG technician's whole job is to produce a tracing a cardiologist can trust, and the striking thing about the role is how much of that trust rests on things you do before the machine ever prints: where exactly you place six chest electrodes, whether the skin was clean and dry, whether the patient was warm and still. A misplaced V-lead does not announce itself — it produces a perfectly clean tracing that quietly suggests a problem the patient does not have, or hides one they do. That is why this exam spends so much of its weight on placement and on artifact rather than on interpretation. The material is unusually durable, because it rests on cardiac electrophysiology and on recording conventions that have been standardized for decades: paper runs at 25 mm per second, calibration is 10 mm per millivolt, a small box is 0.04 seconds, and the P wave has always meant atrial depolarization. Learn why the conduction system fires in the order it does and the answers stay correct as clinical guidance is revised. These free practice questions cover heart anatomy and conduction, 12-lead placement, rhythm identification, artifact troubleshooting, and patient safety in English, Simplified Chinese, and Spanish, with a full explanation for every answer. Every rhythm question describes its tracing completely in words — rate, regularity, P waves, PR interval, QRS width — so you can answer it without a picture, which is also the discipline that makes you good at reading real strips.
What the CET covers — and how to study it
Start with the conduction system, because almost everything else on the exam is a consequence of it. Learn the pathway in order — sinoatrial node, internodal tracts, atrioventricular node, bundle of His, right and left bundle branches, Purkinje fibers — and learn the intrinsic rate of each level: around 60 to 100 at the SA node, 40 to 60 at the AV junction, 20 to 40 in the ventricles. That descending ladder explains escape rhythms, and it explains why a rhythm originating lower in the heart is both slower and wider. Attach each waveform to its event: the P wave is atrial depolarization, the QRS is ventricular depolarization, the T wave is ventricular repolarization, and atrial repolarization is hidden inside the QRS. Learn one more idea that the exam keeps returning to in different clothing: the tracing shows electrical activity only, and electrical activity does not prove the heart is pumping. That single distinction is what makes pulseless electrical activity comprehensible and what makes checking the patient, not the monitor, the correct first move.
Then drill placement until it is muscle memory, and drill it by landmark rather than by picture. V1 sits in the fourth intercostal space at the right sternal border and V2 in the fourth at the left sternal border; V4 goes in the fifth intercostal space at the midclavicular line; V3 goes midway between V2 and V4, so it is placed after V4 rather than in numerical order; V5 sits at the anterior axillary line and V6 at the midaxillary line, both level with V4. Practice finding the fourth intercostal space by walking down from the sternal angle, because that is the step people skip and it is the origin of most misplacement. Learn which leads look at which surface — II, III, and aVF inferior; I, aVL, V5, and V6 lateral; V3 and V4 anterior; V1 and V2 septal — and learn that aVR normally produces negative deflections, so a positive aVR is a placement question before it is a clinical one. Finally, learn the adaptations: under breast tissue rather than on it, alternative sites for amputations and dressings, and the habit of noting any variation directly on the tracing so the reader knows what they are looking at.
Study rhythms as a repeatable procedure instead of as a gallery of shapes. Fix the order — rate, regularity, P waves, PR interval, QRS width — and run it identically every time, including on the rhythms you think you recognize instantly. For rate, know both tools and when each applies: the large-box method (300 divided by the number of large boxes between R waves) is fast but only valid when the rhythm is regular, while counting complexes in a six-second strip and multiplying by ten is the method that survives an irregular rhythm. Group the rhythms by origin rather than alphabetically, because origin is what the checklist actually reveals: sinus rhythms have upright P waves in a normal relationship to the QRS; atrial rhythms distort or lose the P wave, as in the sawtooth of flutter or the absent P waves and irregular irregularity of fibrillation; junctional rhythms invert, bury, or displace it; ventricular rhythms abandon the P wave and widen the QRS. Learn the AV blocks by what happens to the PR interval — fixed and long in first degree, progressively lengthening before a dropped beat in Mobitz I, constant with sudden dropped beats in Mobitz II, and completely dissociated in third degree.
Finish with the two domains that decide whether the tracing is usable at all: artifact and professional practice. Learn each artifact by appearance and cause together, because the exam gives you the appearance and wants the cause — a wandering baseline points to loose or dried electrodes, oils on the skin, or movement; a fuzzy irregular baseline points to muscle tremor from shivering, tension, or pain; a uniform pattern of evenly spaced fine spikes points to alternating-current interference from nearby equipment or coiled lead wires; a flat or interrupted trace in specific leads points to a detached electrode or a broken wire. Since the affected leads identify the responsible electrode, get comfortable reasoning backwards from which leads look wrong. Most artifact is prevented rather than corrected, so learn skin preparation properly: clean, dry, avoid bony prominences, check that the gel is moist, and route the wires so they hang without tension. Then hold the professional line the exam keeps testing — two patient identifiers, privacy and draping, standard precautions and equipment disinfection between patients, a qualified interpreter rather than a family member, no diagnosis offered to the patient, immediate escalation of a dangerous tracing, and a tracing that is accurately labeled, annotated where placement varied, and never altered.
FAQ
Do I need a degree to become an EKG technician?
No. This is a vocational credential rather than an academic one. The usual route is a training program — often a few months at a community college, a vocational school, or through a hospital — combined with hands-on practice performing tracings, and then the certification exam. Many people arrive from an adjacent role: nursing assistants, medical assistants, and phlebotomy technicians frequently add EKG because it stacks naturally onto patient-facing skills they already have, and some employers will train an existing employee into the role. Eligibility pathways and what a specific employer will accept do change, so treat the certifying body's own current requirements and your employer's job posting as the authority rather than anything you read second-hand. What the work asks of you personally is a steady, methodical temperament and genuine comfort with patients, since you will be placing electrodes on the chest of someone who is often frightened and who will ask you what their tracing shows.
Am I allowed to tell a patient what their EKG shows?
No, and this is one of the most reliably tested ideas on the whole exam. The technician's job is to produce a technically excellent tracing and to hand it to the provider; interpreting it for the patient is outside the role, even when what you are seeing is obvious to you and even when the patient presses. The professional answer is to say, warmly and without evasion, that the provider will go over the results with them. This is not merely etiquette — a tracing is one input among many, and a technician's aside can send a patient home reassured about something that needed attention. The exam pairs this with its mirror image: recognizing a life-threatening tracing is squarely within your role, and the expected action is to check the patient and get help immediately rather than to finish the recording, tidy up, or decide what the rhythm technically is. Say nothing diagnostic to the patient; say everything, at once, to the clinical team.
Why does the exam care so much about electrode placement?
Because placement is the one error that produces a confident-looking lie. Artifact is honest — a shaking baseline announces that something is wrong and someone will ask for a repeat. An electrode two intercostal spaces too high produces a clean, plausible tracing that misrepresents the electrical view of the heart, and nothing downstream flags it. Each of the six precordial positions is defined by an anatomical landmark rather than by a measurement on the skin, which is why the exam expects you to find the fourth intercostal space by walking down from the sternal angle rather than by eyeballing it, and why V4, V5, and V6 must sit on the same horizontal level rather than following the curve of the ribs. The same logic drives the questions about limb-lead reversal and about adapting placement for breast tissue, amputations, dressings, and children: the landmark is the rule, and the standard placement is a means to that end rather than a ritual.
How do I identify rhythms without being able to see a strip?
By learning the five-step analysis as a checklist rather than learning rhythms as pictures. Every rhythm question in this bank hands you the same five facts a strip would give you — rate, regularity, whether P waves are present and what they look like, the relationship of P waves to QRS complexes, and QRS width — and each named rhythm is simply a distinct combination of those five. Irregularly irregular with no discernible P waves is atrial fibrillation whether you read it in words or off paper. A PR interval that lengthens beat by beat until a QRS is dropped is Wenckebach either way. This is deliberately how the questions are built, and it turns out to be better training than pattern-matching pictures, because on a real strip the pattern you half-recognize is exactly where mistakes come from. Work the checklist in the same order every time and the wide-versus-narrow QRS distinction — the one that separates a ventricular problem from a supraventricular one — falls out of it automatically.
What is the difference between an EKG technician, a monitor tech, and a cardiovascular technologist?
They sit at different points on the same ladder. An EKG technician performs the recording — placing electrodes, obtaining a diagnostic-quality 12-lead tracing, and often applying Holter monitors and assisting with stress testing. A monitor technician watches continuous telemetry for a unit full of patients and escalates changes, which is more sustained vigilance and less patient contact. A cardiovascular technologist has typically completed a longer program and works in more invasive territory, such as the catheterization lab or echocardiography. The practical point for someone choosing a starting place is that the EKG role has the shortest path in and transfers well: the anatomy, conduction, and rhythm recognition you learn here are the same foundations the other roles build on, which is why so many people treat it as a first rung rather than a destination. Job titles and duties are assigned by employers and vary between facilities, so read the posting rather than assuming the title means the same thing everywhere.