SCFHS Biomedical Engineering & Medical Devices exam questions

The Biomedical Engineering & Medical Devices exam in every GCC country

From each regulator's own exam pages; anything a regulator does not publish says so. Assessment mode also depends on your licence title, so confirm your route on your eligibility notice.

12 worked Biomedical Engineering & Medical Devices practice questions

Original exam-style questions from the bank, spread across the blueprint domains. They are not real or recalled exam questions. Try each one, then open the answer for the rationale and reference. None of them appear in the free mock exam, so reading them will not spoil it.

1. Question 1 · Advanced Electronics and Electricity

   A first-order RC low-pass filter uses a 1.6 kilohm resistor and a 0.1 microfarad capacitor. What is the approximate cut-off frequency?

   1. AAbout 100 Hz
   2. BAbout 1 kHz
   3. CAbout 10 kHz
   4. DAbout 6.3 kHz
   Show answer and explanation

   Correct answer: B. About 1 kHz

   fc = 1 / (2 pi R C) = 1 / (2 x 3.14 x 1600 x 0.0000001), which is about 995 Hz. 100 Hz and 10 kHz are off by a factor of ten, and 6.3 kHz is 2 pi x 1 kHz, which confuses angular frequency with frequency in hertz.

   Reference: Horowitz and Hill, The Art of Electronics, 3rd ed., 2015

2. Question 2 · Anatomy and Physiology

   A technician is calibrating an ECG simulator. Which ECG component represents depolarisation of the ventricles?

   1. AThe P wave
   2. BThe QRS complex
   3. CThe T wave
   4. DThe PR segment
   Show answer and explanation

   Correct answer: B. The QRS complex

   Ventricular depolarisation produces the QRS complex. The P wave is atrial depolarisation, the T wave is ventricular repolarisation, and the PR segment is the delay at the AV node.

   Reference: Guyton and Hall, Textbook of Medical Physiology, 14th ed., 2020

3. Question 3 · Anatomy and Physiology

   A patient monitor displays a blood pressure of 120/90 mmHg. What is the approximate mean arterial pressure?

   1. A100 mmHg
   2. B105 mmHg
   3. C90 mmHg
   4. D110 mmHg
   Show answer and explanation

   Correct answer: A. 100 mmHg

   MAP is diastolic plus one third of the pulse pressure: 90 + (30 / 3) = 100 mmHg. 105 and 110 mmHg overweight the systolic value, and 90 mmHg is only the diastolic pressure.

   Reference: Guyton and Hall, Textbook of Medical Physiology, 14th ed., 2020

4. Question 4 · Patient Safety, Electrical Safety and Hazards

   Which patient leakage current limit in normal condition applies to a type CF applied part under the general standard for medical electrical equipment?

   1. A100 microamperes
   2. B500 microamperes
   3. C10 microamperes
   4. D5 milliamperes
   Show answer and explanation

   Correct answer: C. 10 microamperes

   Type CF applied parts, used directly on the heart, are limited to 10 microamperes in normal condition and 50 in single fault. 100 and 500 microamperes are the type BF limits, and 5 milliamperes is the earth leakage limit.

   Reference: IEC 60601-1:2005+AMD1:2012+AMD2:2020

5. Question 5 · Physics

   Hydrogen protons precess at about 42.58 MHz per tesla. What is the approximate Larmor frequency on a 3 T MRI scanner?

   1. AAbout 64 MHz
   2. BAbout 43 MHz
   3. CAbout 128 MHz
   4. DAbout 255 MHz
   Show answer and explanation

   Correct answer: C. About 128 MHz

   Frequency is proportional to field strength: 42.58 x 3 is about 128 MHz. 64 MHz applies to 1.5 T, 43 MHz to 1 T, and 255 MHz to 6 T.

   Reference: Bushberg et al., The Essential Physics of Medical Imaging, 4th ed., 2021

6. Question 6 · Practical Experience

   A pressure gauge used to calibrate NIBP monitors is itself being calibrated. Which reference arrangement is acceptable?

   1. AAnother working gauge of the same make and age
   2. BThe device under test used as its own reference
   3. CA reference standard traceable to a national standard with a test uncertainty ratio of at least 4 to 1
   4. DA reference accurate to the same level as the gauge under test
   Show answer and explanation

   Correct answer: C. A reference standard traceable to a national standard with a test uncertainty ratio of at least 4 to 1

   Calibration needs a traceable reference clearly more accurate than the unit under test, usually at least four times. A similar gauge, or the device itself, or an equal-accuracy reference cannot show the error reliably.

   Reference: ANSI/NCSL Z540.3-2006, Requirements for calibration of measuring and test equipment

7. Question 7 · Biomedical Equipment Technology

   A ventilator in volume control shows a high peak pressure alarm while the plateau pressure remains normal. Which cause fits?

   1. AReduced lung compliance, for example from pulmonary oedema
   2. BRaised airway resistance, such as a kinked tube
   3. CA leak in the breathing circuit
   4. DA disconnected patient circuit
   Show answer and explanation

   Correct answer: B. Raised airway resistance, such as a kinked tube

   When the peak rises but the plateau does not, the problem is in the airways or tube, so resistance has risen. Poor compliance raises both pressures. A leak or a disconnection lowers the pressure and gives a low-pressure alarm.

   Reference: Bronzino, The Biomedical Engineering Handbook, 4th ed. (2015)

8. Question 8 · Advanced Electronics and Electricity

   A non-inverting amplifier has a 90 kilohm feedback resistor and a 10 kilohm resistor to ground. What is its gain?

   1. A9
   2. B-9
   3. C10
   4. D100
   Show answer and explanation

   Correct answer: C. 10

   The gain of a non-inverting amplifier is 1 + Rf/Rg = 1 + 90/10 = 10. The value 9 forgets the 1, and -9 is the gain of an inverting stage. The value 100 does not follow from the formula.

   Reference: Sedra and Smith, Microelectronic Circuits, 7th ed. (2014)

9. Question 9 · Anatomy and Physiology

   An ECG simulator is set to a rhythm with no visible P waves and an irregularly irregular ventricular rate. Which rhythm is this?

   1. ASinus arrhythmia
   2. BThird-degree heart block
   3. CAtrial flutter with a fixed block
   4. DAtrial fibrillation
   Show answer and explanation

   Correct answer: D. Atrial fibrillation

   Absent P waves with a chaotic ventricular rate are the pattern of atrial fibrillation. Sinus arrhythmia keeps P waves. Complete heart block has a regular slow ventricular rhythm, and flutter with a fixed block gives a regular rate with sawtooth waves.

   Reference: Webster, Medical Instrumentation: Application and Design, 4th ed. (2010)

10. Question 10 · Chemistry

    In the Spaulding classification, which item category requires sterilisation?

    1. ACritical items that enter sterile tissue, such as surgical instruments
    2. BSemi-critical items that touch mucous membranes, such as a bronchoscope
    3. CNon-critical items that touch intact skin, such as a blood pressure cuff
    4. DEnvironmental surfaces such as bed rails
    Show answer and explanation

    Correct answer: A. Critical items that enter sterile tissue, such as surgical instruments

    Items that penetrate sterile tissue or the vascular system carry the highest infection risk and must be sterilised. Semi-critical items need at least high-level disinfection. Non-critical items need low-level cleaning or disinfection, and surfaces are cleaned.

    Reference: CDC Guideline for Disinfection and Sterilization in Healthcare Facilities (2008)

11. Question 11 · Professionalism

    A ventilator that delivered an excess pressure has injured a patient. What should the technician do first?

    1. ARepair and recalibrate it before the review so it returns quickly
    2. BQuarantine it with settings and logs intact, then report the event to the manager
    3. CClear the event log to remove the alarm history
    4. DReturn it to the vendor without telling anyone
    Show answer and explanation

    Correct answer: B. Quarantine it with settings and logs intact, then report the event to the manager

    The device is evidence and must be quarantined with settings and logs intact so that the cause can be found, and the event must be reported. Repairing it, clearing the log or sending it away destroys evidence and delays learning.

    Reference: Dyro, Clinical Engineering Handbook (2004)

12. Question 12 · Patient Safety, Electrical Safety and Hazards

    Which action best reduces fire risk during head and neck surgery that uses electrosurgery?

    1. ARaise the oxygen concentration around the surgical site
    2. BAllow alcohol prep solution to pool under the drapes
    3. CLet skin prep dry and keep oxygen as low as is safe
    4. DRun the unit at its highest power for most cutting
    Show answer and explanation

    Correct answer: C. Let skin prep dry and keep oxygen as low as is safe

    A fire needs an ignition source, fuel and an oxidiser. Wet alcohol is fuel and extra oxygen makes the fire burn faster, so both are limited. Pooled solution and unnecessarily high power increase the hazard.

    Reference: ASA Practice Advisory for the Prevention and Management of Operating Room Fires (2013)

Biomedical Engineering & Medical Devices reference books and guidelines

Every question in this bank names the textbook or guideline its answer rests on. These are the sources our Biomedical Engineering & Medical Devices questions cite most often - the reading list to revise from alongside the bank.

Where your regulator publishes a reading list, use the editions it names. Exam questions are not taken from any one book.