CBET (Certified Biomedical Equipment Technician) Exam — Questions and Answers

Question 1: Which logic gate outputs HIGH only when all inputs are HIGH?

AND gate (Correct answer)
OR gate
NOR gate
NAND gate

Correct answer: AND gate

An AND gate produces a HIGH output only when every input is simultaneously HIGH.

Question 2: An infusion pump displays a 'door open' alarm even though the door is fully closed and latched. What troubleshooting approach should you take first?

Inspect the door latch mechanism and door switch for mechanical wear or debris (Correct answer)
Replace the IV tubing set
Update the pump firmware
Replace the entire pump

Correct answer: Inspect the door latch mechanism and door switch for mechanical wear or debris

A false 'door open' alarm indicates the door switch or latch mechanism is not properly activating when closed.

Question 3: Which of the following best describes the function of an optocoupler (optoisolator) in medical equipment?

Transmitting signals between circuits while maintaining electrical isolation (Correct answer)
Measuring light intensity for phototherapy
Converting optical signals to radio frequency
Amplifying weak biological signals

Correct answer: Transmitting signals between circuits while maintaining electrical isolation

An optocoupler uses an LED and photodetector to transmit signals between electrically isolated circuits, maintaining patient safety.

Question 4: A technician is performing annual PM on a hospital bed. Which safety check is MOST critical for patient fall prevention?

Testing siderail locking mechanisms for secure engagement (Correct answer)
Inspecting the mattress cover for tears
Verifying the bed's Trendelenburg angle accuracy
Calibrating the bed's weight scale

Correct answer: Testing siderail locking mechanisms for secure engagement

Siderail locking mechanism failure is directly linked to patient falls, making it the highest-priority safety check during hospital bed PM.

Question 5: Which NFPA 99 health care facility category requires the highest level of medical gas system redundancy and emergency backup?

Category 3
Category 1 (Correct answer)
Category 2
Category 4

Correct answer: Category 1

Category 1 facilities (e.g., operating rooms, ICUs) require the highest redundancy because failure of equipment could cause major injury or death.

Question 6: A ventilator is set to Volume-Controlled Ventilation (VCV) at 500 mL tidal volume. The high peak pressure alarm activates with every breath. Plateau pressure measured during an inspiratory hold is normal. What is the most likely cause?

A leak in the ventilator circuit
Increased airway resistance (e.g., bronchospasm or secretions) (Correct answer)
Decreased lung compliance (stiff lungs)
Auto-PEEP from insufficient expiratory time

Correct answer: Increased airway resistance (e.g., bronchospasm or secretions)

In VCV, peak pressure reflects both airway resistance and lung compliance, while plateau pressure (measured during no-flow inspiratory hold) reflects compliance only. A high peak pressure with a NORMAL plateau pressure indicates increased airway resistance — the lungs can accept the volume, but the airway is obstructed. If compliance were decreased, both peak AND plateau would be elevated.

Question 7: Multiple physiologic monitors on the same nursing unit are showing intermittent signal artifact on ECG waveforms. Patient leads and cables have been replaced. What environmental factor should be investigated?

Ambient sound level
Humidity level
Room lighting level
Electromagnetic interference from nearby equipment or construction (Correct answer)

Correct answer: Electromagnetic interference from nearby equipment or construction

Intermittent ECG artifact affecting multiple monitors suggests electromagnetic interference from a shared environmental source.

Question 8: Which color-coded label is assigned to nitrous oxide piping in a US hospital per NFPA 99 and CGA standards?

Gray
Blue
Green
Light blue (Correct answer)

Correct answer: Light blue

Nitrous oxide piping is identified with a light blue label per CGA C-9 and NFPA 99 to distinguish it from oxygen (green) and medical air (yellow).

Question 9: What component in an electrical circuit allows current to flow in only one direction?

Inductor
Diode (Correct answer)
Capacitor
Resistor

Correct answer: Diode

A diode is a semiconductor device that allows current to flow in one direction (forward bias) while blocking current in the reverse direction.

Question 10: What is a medical gas manifold system and how does it ensure continuous gas supply?

A dual-bank arrangement of cylinders with automatic switchover between primary and reserve banks (Correct answer)
A mixing chamber that combines multiple gases
A pressure boosting system
A single large cylinder connected directly to the pipeline

Correct answer: A dual-bank arrangement of cylinders with automatic switchover between primary and reserve banks

A manifold uses two banks with automatic switchover to ensure uninterrupted supply.

Question 11: In an op-amp configured as an inverting amplifier with Rf = 100 kΩ and Rin = 10 kΩ, the voltage gain is:

+0.1
+10
-10 (Correct answer)
-0.1

Correct answer: -10

The inverting amplifier gain is -Rf/Rin = -100kΩ/10kΩ = -10, where the negative sign indicates phase inversion.

Question 12: In which of the following scenarios is a device fault more likely to occur than a use mistake?

Blurry ultrasound imagery from a newly inspected handheld ultrasound machine
Noisy ECG readings near high-powered electrical equipment
A nurse station not receiving patient information from vital signs monitor (Correct answer)
A medication overdose due to a misconfigured infusion pump

Correct answer: A nurse station not receiving patient information from vital signs monitor

A nurse station not receiving patient information from a vital signs monitor strongly indicates a technical malfunction or device fault. This could be due to a communication error, network issue, or internal hardware problem with the monitor or the receiving system. The other scenarios are more likely attributable to user error or environmental factors rather than an inherent device fault.

Question 13: What is the primary physiological purpose of Positive End-Expiratory Pressure (PEEP) in a mechanically ventilated patient?

To deliver supplemental oxygen above the set FiO₂
To reduce the work of breathing by lowering peak inspiratory pressure
To prevent alveolar collapse (atelectasis) at end-expiration and improve oxygenation (Correct answer)
To increase minute ventilation by extending inspiratory time

Correct answer: To prevent alveolar collapse (atelectasis) at end-expiration and improve oxygenation

PEEP maintains positive airway pressure throughout the expiratory phase, keeping alveoli open and preventing end-expiratory collapse. This recruits more alveolar surface area for gas exchange, improving oxygenation (PaO₂). It does not change minute ventilation directly, reduce peak pressure, or affect FiO₂ delivery.

Question 14: Which type of fire extinguisher is appropriate for electrical equipment fires in a biomedical equipment area?

Class C (CO2 or dry chemical) (Correct answer)
Class A (water)
Class B (foam)
Class D (dry powder)

Correct answer: Class C (CO2 or dry chemical)

Class C extinguishers use non-conductive agents like CO2 or dry chemical, making them safe for energized electrical equipment fires.

Question 15: What type of pump mechanism do most volumetric IV infusion pumps use to deliver fluids?

Diaphragm pump
Centrifugal pump
Peristaltic pump mechanism that sequentially compresses IV tubing (Correct answer)
Gear pump

Correct answer: Peristaltic pump mechanism that sequentially compresses IV tubing

Most volumetric IV infusion pumps use a peristaltic mechanism that sequentially compresses the tubing to push fluid forward.

Question 16: Which law governs the relationship between pressure, volume, and temperature for an ideal gas, relevant to medical gas cylinders?

Bernoulli's Principle
Ohm's Law
The Combined Gas Law (Boyle's + Charles' Laws) (Correct answer)
Poiseuille's Law

Correct answer: The Combined Gas Law (Boyle's + Charles' Laws)

The Combined Gas Law (P1V1/T1 = P2V2/T2) describes how pressure, volume, and temperature interrelate in gas cylinders used in medical settings.

Question 17: The output impedance of a device should ideally be low because:

It minimizes signal voltage drop when driving a load (Correct answer)
It increases current draw from the power supply
It prevents electromagnetic interference
It increases the device's power consumption

Correct answer: It minimizes signal voltage drop when driving a load

Low output impedance ensures minimal voltage drop across the source impedance when current flows, maintaining signal integrity to the load.

Question 18: A fluoroscopy unit's automatic exposure control (AEC) is not functioning. What is the main risk?

Images will be black
Patient may receive excessive radiation dose (Correct answer)
The PACS connection will drop
The table will not move

Correct answer: Patient may receive excessive radiation dose

AEC modulates dose to maintain adequate image quality; without it, fixed high technique settings can significantly over-irradiate the patient.

Question 19: What is an operating room integration system and what does it manage?

A surgery scheduling system
A room temperature control system
A surgical inventory system
A system that centrally controls video, audio, and data from multiple surgical devices within the OR (Correct answer)

Correct answer: A system that centrally controls video, audio, and data from multiple surgical devices within the OR

OR integration systems manage routing of video from surgical cameras, audio, room controls, recording, and documentation.

Question 20: A BMET is performing electrical safety testing on a device and measures patient leakage current that exceeds allowable limits under ANSI/AAMI ES60601-1. The MOST appropriate next step is to:

Notify only the nursing staff and let them decide on continued use
Return the device to service and schedule follow-up testing in 30 days
Increase the ground resistance to compensate for the high leakage
Remove the device from service, document findings, and initiate repair before return to use (Correct answer)

Correct answer: Remove the device from service, document findings, and initiate repair before return to use

A device that fails electrical safety testing must be removed from service immediately, the failure documented, and the device repaired and retested before being returned to patient use.

Question 21: What is the normal range for adult resting respiratory rate in breaths per minute?

6-10
30-40
12-20 (Correct answer)
22-30

Correct answer: 12-20

The normal adult resting respiratory rate is 12-20 breaths per minute, which is a vital sign commonly monitored by patient monitoring equipment.

Question 22: Which standard governs the safe use of electrical equipment in patient care areas in US hospitals?

NEC Article 517
NFPA 101
NFPA 99 (Correct answer)
OSHA 1910.303

Correct answer: NFPA 99

NFPA 99 (Health Care Facilities Code) specifically addresses electrical safety, medical gas systems, and other hazards in healthcare facilities.

Question 23: Which of the following conventional ECG leads allows you to see the heart's inferior wall?

I
aVF (Correct answer)
V1
aVR

Correct answer: aVF

The inferior wall of the heart is best viewed by the ECG leads II, III, and aVF. These leads are positioned to detect electrical activity from the inferior aspect of the heart. Lead aVF specifically stands for 'augmented vector foot' and provides a clear electrical perspective looking up from the foot towards the heart's inferior surface.

Question 24: During an electrical safety test, a patient monitor passes all leakage current tests under normal conditions but fails under single-fault (open ground) condition. What does this indicate?

The device has adequate basic insulation but relies on the ground connection for safety - internal insulation may be degrading (Correct answer)
The device needs a new power cord only
The safety analyzer is malfunctioning
The device is safe to use as-is

Correct answer: The device has adequate basic insulation but relies on the ground connection for safety - internal insulation may be degrading

Passing under normal conditions but failing under open ground indicates internal insulation degradation that the ground path currently compensates for.

Question 25: A motorized cervical traction unit is set to apply 15 lbs of traction. During PM, the BMET's tension scale reads 11 lbs at the 15 lb setting. What is the percentage error, and does this require repair before returning to service?

26.7% error — no, traction devices have a ±30% tolerance by design
13.3% error — acceptable, as traction forces are inherently variable due to patient movement
4 lbs error — only absolute lb errors matter; percentages are not used for traction PM
26.7% error — yes, this exceeds the typical ±10% tolerance and requires repair (Correct answer)

Correct answer: 26.7% error — yes, this exceeds the typical ±10% tolerance and requires repair

Percentage error = (|measured − set| / set) × 100 = (|11 − 15| / 15) × 100 = (4/15) × 100 = 26.7%. Most traction device PM protocols specify a ±10% accuracy tolerance. A 26.7% error significantly exceeds this and requires the device to be taken out of service for repair or recalibration. Applying less force than intended could render therapy ineffective; more importantly, accuracy matters for patient safety.

Question 26: Which component in an X-ray tube is the source of electrons?

Anode disc
Glass envelope
Cathode filament (Correct answer)
Rotor bearing

Correct answer: Cathode filament

The cathode filament is heated by current until thermionic emission releases electrons, which are then accelerated toward the anode.

Question 27: A ventilator's delivered tidal volume is consistently 15-20% lower than the set value. The circuit has been checked for leaks and none were found. What should you investigate next?

The patient's lung compliance
The oxygen blender only
The ventilator's display screen
The flow sensor calibration and the expiratory valve function (Correct answer)

Correct answer: The flow sensor calibration and the expiratory valve function

With no circuit leaks, a consistent under-delivery suggests flow sensor drift or expiratory valve malfunction.

Question 28: When troubleshooting a patient monitor displaying 'Lead Off' for ECG, what should a biomedical technician check?

The monitor software version
The monitor battery level
The room temperature
The electrode contact quality, lead wire integrity, and cable connections from patient to monitor (Correct answer)

Correct answer: The electrode contact quality, lead wire integrity, and cable connections from patient to monitor

'Lead Off' means a break in the electrical circuit between the patient's skin and the ECG amplifier input.

Question 29: What is the primary function of the inspiratory-to-expiratory (I:E) ratio setting on a mechanical ventilator?

It sets the tidal volume delivered with each breath
It adjusts the peak airway pressure alarm threshold
It controls the proportion of time spent in inhalation versus exhalation during each breath cycle (Correct answer)
It determines the oxygen concentration in delivered gas

Correct answer: It controls the proportion of time spent in inhalation versus exhalation during each breath cycle

The I:E ratio defines how the breath cycle is divided, affecting gas distribution and hemodynamic impact; normal is approximately 1:2.

Question 30: What is the function of a medical vacuum system in a hospital, and what minimum vacuum level must it maintain?

Provides suction for clinical procedures maintaining at least 12 inches Hg at the most remote outlet (Correct answer)
Creates negative pressure rooms at 1 inch Hg
Removes dust at 5 inches Hg
Removes smoke during surgery at 20 inches Hg

Correct answer: Provides suction for clinical procedures maintaining at least 12 inches Hg at the most remote outlet

Medical vacuum provides suction for clinical procedures and must maintain a minimum of 12 inches Hg per NFPA 99.

Question 31: In troubleshooting a medical device power supply, you measure 0V DC output but 120V AC input is present. Which component is most likely failed?

Input fuse
Bridge rectifier or filter capacitor (Correct answer)
Wall outlet
Power cord

Correct answer: Bridge rectifier or filter capacitor

With AC input present but no DC output, the AC-to-DC conversion stage has failed. The bridge rectifier or filter capacitor are the most likely culprits.

Question 32: Which unit measures absorbed radiation dose in tissue?

Sievert (Sv)
Roentgen (R)
Becquerel (Bq)
Gray (Gy) (Correct answer)

Correct answer: Gray (Gy)

The Gray is the SI unit of absorbed dose, defined as one joule of energy deposited per kilogram of tissue.

Question 33: Under the Health Insurance Portability and Accountability Act (HIPAA), a BMET who accesses patient data stored on a medical device must:

Report all accessed data to the hospital's compliance officer
Encrypt and email data to the device manufacturer for analysis
Copy the data for equipment maintenance records
Access only the minimum necessary information and follow facility data handling policies (Correct answer)

Correct answer: Access only the minimum necessary information and follow facility data handling policies

HIPAA's minimum necessary standard requires workforce members to access only the protected health information needed to perform their job function.

Question 34: Which mechanism allows a double-lumen endobronchial tube to facilitate one-lung ventilation during thoracic surgery?

Separate lumens allow one lung to be isolated and collapsed while the other is ventilated (Correct answer)
It delivers 100% oxygen to both lungs simultaneously at high flow
A balloon in the trachea seals off the airway above the carina
It uses CPAP on one side and PEEP on the other to equalize pressures

Correct answer: Separate lumens allow one lung to be isolated and collapsed while the other is ventilated

Each lumen opens to one bronchus; clamping one lumen collapses that lung for surgical access while the other continues ventilation.

Question 35: In ultrasound imaging, what physical principle allows tissue boundaries to be visualized?

Absorption of X-ray photons
Nuclear magnetic resonance
Reflection of sound waves at acoustic impedance mismatches (Correct answer)
Fluorescence under UV light

Correct answer: Reflection of sound waves at acoustic impedance mismatches

Sound waves reflect at interfaces between tissues of different acoustic impedance; the transducer detects these echoes to reconstruct an image.

Question 36: Ultrasound transducers used in diagnostic imaging are based on the piezoelectric effect. What does this effect describe?

The refraction of sound waves at tissue boundaries with differing acoustic impedance
The conversion between mechanical stress/deformation and electrical charge in certain crystals (Correct answer)
The absorption of sound energy by dense biological tissue such as bone
The generation of heat when a material is exposed to high-frequency sound

Correct answer: The conversion between mechanical stress/deformation and electrical charge in certain crystals

The piezoelectric effect (discovered by Pierre Curie) describes the ability of certain materials (quartz, PZT ceramics) to generate an electric charge when mechanically deformed (direct piezoelectric effect) and, conversely, to mechanically deform when an electric field is applied (converse piezoelectric effect). Ultrasound transducers exploit both: voltage pulses create sound waves (transmit), and returning echo waves create voltages (receive).

Question 37: What does OSHA require regarding bloodborne pathogen exposure protection for biomedical technicians?

Only hand washing is required
Technicians must purchase own PPE
No specific requirements exist
Employers must provide an exposure control plan, training, PPE, hepatitis B vaccination, and post-exposure procedures (Correct answer)

Correct answer: Employers must provide an exposure control plan, training, PPE, hepatitis B vaccination, and post-exposure procedures

OSHA's Bloodborne Pathogens Standard requires comprehensive employer-provided protection for workers with occupational exposure.

Question 38: A hospital wants to segment its biomedical device network from the administrative network. Which technology accomplishes this at Layer 2?

SNMP (Simple Network Management Protocol)
NAT (Network Address Translation)
DNS (Domain Name System)
VLAN (Virtual LAN) (Correct answer)

Correct answer: VLAN (Virtual LAN)

VLANs logically segment networks at Layer 2 (Data Link), isolating biomedical device traffic from administrative systems.

Question 39: What is the purpose of the return electrode monitoring (REM) system on an electrosurgical unit?

To monitor the surgeon's hand position
To control cutting depth
To measure total energy delivered
To continuously verify adequate contact of the dispersive electrode pad to prevent burns (Correct answer)

Correct answer: To continuously verify adequate contact of the dispersive electrode pad to prevent burns

REM monitors impedance between the split-pad sections, alarming and disabling output if contact degrades.

Question 40: Which Spaulding classification category requires sterilization rather than just high-level disinfection?

Critical items (Correct answer)
General-use items
Semicritical items
Noncritical items

Correct answer: Critical items

Critical items enter sterile tissue or the vascular system and must be sterilized to eliminate all microorganisms including spores.

Question 41: What safety system prevents connecting a medical gas cylinder to the wrong yoke or regulator?

Pin Index Safety System (PISS) (Correct answer)
The cylinder label
The pressure gauge
Color coding only

Correct answer: Pin Index Safety System (PISS)

PISS uses specific pin positions on the cylinder valve that correspond to holes on the yoke, mechanically preventing wrong gas connection.

Question 42: A portable X-ray unit fails to produce an exposure when triggered. The BMET confirms the battery is fully charged. What should be checked next?

Focal spot size
Handswitch and exposure control circuitry (Correct answer)
High-voltage transformer primary winding
Collimator lamp

Correct answer: Handswitch and exposure control circuitry

The handswitch and exposure control circuit initiate the exposure sequence; a fault here will prevent triggering even with adequate power.

Question 43: What is the purpose of an equipment management plan in a healthcare facility?

To schedule equipment cleaning only
To track equipment purchase prices
To manage cafeteria equipment
To establish a systematic program for managing medical equipment throughout its lifecycle (Correct answer)

Correct answer: To establish a systematic program for managing medical equipment throughout its lifecycle

An equipment management plan provides a comprehensive approach to managing medical equipment from selection through retirement.

Question 44: What is the typical frequency range of an ECG amplifier's bandwidth for diagnostic-quality monitoring?

10-1000 Hz
0.05-150 Hz (Correct answer)
0.5-40 Hz
1-500 Hz

Correct answer: 0.05-150 Hz

Diagnostic-quality ECG requires 0.05-150 Hz bandwidth to capture all waveform components accurately.

Question 45: A nurse reports an infusion pump is alarming for "Downstream Occlusion." The BMET visually inspects the IV tubing from the pump to the patient and finds no visible kinks or clamps. What is the MOST appropriate next step in troubleshooting?

Disconnect the tubing from the patient and attempt to run a small volume of fluid into a container. (Correct answer)
Reboot the infusion pump to reset the software.
Instruct the nurse to increase the infusion rate to try and clear the line.
Immediately replace the pump's internal pressure sensor.

Correct answer: Disconnect the tubing from the patient and attempt to run a small volume of fluid into a container.

This step effectively isolates the problem. If the pump can infuse into a container without alarming, the issue is likely with the patient's IV catheter or access site (e.g., a clot or positional infiltration). If it still alarms, the problem is with the pump or the disposable tubing set. This is a critical and non-invasive troubleshooting step that differentiates a device problem from a clinical one.

Question 46: An anesthesia machine is failing its automatic low-pressure leak test. The technician has already replaced the entire external breathing circuit with a known good set, but the failure persists. Which of the following is the MOST likely internal component to investigate next for a leak?

The main power supply board.
The CO2 absorber canister and its seals. (Correct answer)
The vaporizer interlock mechanism.
The oxygen flowmeter.

Correct answer: The CO2 absorber canister and its seals.

The CO2 absorber canister is a critical part of the low-pressure breathing circuit. Its seals can easily become compromised when the canister is changed or if it is cracked, making it one of the most common sources of leaks within the machine after the external circuit has been ruled out.

Question 47: What is the normal resting heart rate range for a healthy adult?

100-120 bpm
80-140 bpm
40-50 bpm
60-100 bpm (Correct answer)

Correct answer: 60-100 bpm

A normal resting heart rate for adults ranges from 60 to 100 beats per minute, a fundamental parameter monitored by cardiac equipment.

Question 48: The Frank-Starling law of the heart states that cardiac output increases when:

Heart rate decreases below 60 bpm
Sympathetic tone is withdrawn
Ventricular filling volume (preload) increases (Correct answer)
Afterload exceeds systemic vascular resistance

Correct answer: Ventricular filling volume (preload) increases

The Frank-Starling mechanism describes how increased end-diastolic volume stretches myocardial fibers, resulting in a stronger contraction and greater stroke volume.

Question 49: Which MRI safety zone requires strict ferromagnetic screening of all personnel and equipment?

Zone III
Zone II
Zone IV (Correct answer)
Zone I

Correct answer: Zone IV

Zone IV is the MRI scanner room itself, where the static magnetic field is always present, requiring the strictest screening.

Question 50: An op-amp configured with the non-inverting input connected to a voltage divider and output fed back to the inverting input is functioning as a:

Comparator
Differentiator
Voltage follower (buffer) (Correct answer)
Voltage regulator

Correct answer: Voltage follower (buffer)

When the output feeds directly back to the inverting input with no other feedback components, the op-amp becomes a unity-gain voltage follower.

Question 51: A patient-controlled analgesia (PCA) pump must include which safety feature to prevent accidental overdose?

A lockout interval that disables bolus delivery for a set time after each dose (Correct answer)
A variable drip rate adjusted by nursing staff every hour
An automatic increase in dose when the patient presses the button repeatedly
A pressure sensor that detects IV line occlusion only

Correct answer: A lockout interval that disables bolus delivery for a set time after each dose

The lockout interval enforces a mandatory waiting period between boluses, preventing the patient from receiving dangerous cumulative doses.

Question 52: A biomedical engineering department is developing an Alternative Equipment Maintenance (AEM) program. According to The Joint Commission, which of the following is a critical requirement for equipment included in an AEM program?

Scheduled maintenance completion for high-risk equipment in an AEM program must be 100%. (Correct answer)
AEM programs can only be applied to non-medical, facility-related equipment.
The manufacturer must provide written approval before a device can be placed on an AEM.
All equipment on an AEM program must be less than two years old.

Correct answer: Scheduled maintenance completion for high-risk equipment in an AEM program must be 100%.

The Joint Commission requires that scheduled maintenance for high-risk medical equipment, including life-support devices, must have a 100% completion rate, regardless of whether it is part of a standard or an Alternative Equipment Maintenance (AEM) program. This ensures that critical devices are properly maintained to prevent failure.

Question 53: A harmonic scalpel generates heat through which mechanism?

Radiofrequency current passed through tissue
Laser photon absorption by chromophores
Resistive heating of a metal blade
Ultrasonic vibration causing molecular friction within tissue (Correct answer)

Correct answer: Ultrasonic vibration causing molecular friction within tissue

Harmonic scalpels use ultrasonic vibration (typically 55,500 Hz) that causes rapid protein denaturation through molecular friction, achieving cutting and coagulation simultaneously.

Question 54: What is an FDA medical device recall and what are the three recall classes?

A recall means all devices are permanently removed
Recalls correct or remove defective devices; Class I is most serious, Class II is less serious, Class III is unlikely to cause harm (Correct answer)
Recalls only apply to implantable devices
Only Class I requires action

Correct answer: Recalls correct or remove defective devices; Class I is most serious, Class II is less serious, Class III is unlikely to cause harm

Recalls address defective devices. Class I: serious health consequences/death. Class II: temporary/reversible. Class III: not likely to cause harm.

Question 55: A ventilator's tidal volume display reads 500 mL but a calibrated test lung measurement shows only 420 mL. What is the most likely cause?

Flow sensor calibration drift (Correct answer)
Incorrect PEEP setting
Faulty inspiratory valve
Low oxygen supply pressure

Correct answer: Flow sensor calibration drift

Flow sensor drift is the most common cause of tidal volume display inaccuracy when the set and delivered volumes differ consistently.

Question 56: Which tool is used to measure ground wire resistance during electrical safety testing?

Clamp meter only
Electrical safety analyzer (Correct answer)
Standard digital multimeter
Hipot tester

Correct answer: Electrical safety analyzer

An electrical safety analyzer (such as a Fluke or Rigel unit) measures ground resistance, leakage currents, and line voltage in one instrument.

Question 57: What is pulse transit time and how are newer patient monitors using it?

The time a pulse oximeter takes to display
The time between ECG spike and respiration
The time for a pulse wave to travel between two arterial sites, being explored for continuous cuff-less blood pressure estimation (Correct answer)
The time between two heartbeats

Correct answer: The time for a pulse wave to travel between two arterial sites, being explored for continuous cuff-less blood pressure estimation

PTT inversely correlates with blood pressure and enables continuous cuff-less BP estimation.

Question 58: Why is it important to verify alarm settings on a patient monitor at the beginning of each patient encounter?

Alarms are only important in the ICU
Alarms are preset and never need adjustment
Alarm limits must be individualized to prevent missed events and alarm fatigue from false alarms (Correct answer)
Default settings are always appropriate

Correct answer: Alarm limits must be individualized to prevent missed events and alarm fatigue from false alarms

Alarm limits must be individualized because default or previous patient settings may not be appropriate.

Question 59: A portable X-ray unit's collimator is found to be misaligned during PM. Why is this clinically significant?

Misalignment exposes patients to unnecessary radiation outside the intended field (Correct answer)
It overheats the X-ray tube
It makes images appear blurry
It increases patient dose to the intended field only

Correct answer: Misalignment exposes patients to unnecessary radiation outside the intended field

Collimator misalignment means the radiation field does not match the light field, potentially exposing unintended anatomy and violating ALARA principles.

Question 60: What does a positive result on a Bowie-Dick test indicate?

Biological indicator growth detected
Air removal failure in the pre-vacuum autoclave (Correct answer)
Successful sterilization of the load
Chemical indicator color change failed

Correct answer: Air removal failure in the pre-vacuum autoclave

A positive (failed) Bowie-Dick test indicates that air was not properly removed from the chamber, which would prevent steam penetration and sterilization.

Question 61: What is the function of an anesthesia workstation's gas delivery system and how does it ensure patient safety?

It precisely mixes and delivers gases with safety systems including oxygen ratio monitoring and agent identification (Correct answer)
It only delivers oxygen
It monitors brain activity
It controls room ventilation

Correct answer: It precisely mixes and delivers gases with safety systems including oxygen ratio monitoring and agent identification

The gas delivery system precisely controls the mixture of gases and anesthetic agents with multiple safety mechanisms.

Question 62: In Pressure-Controlled Ventilation (PCV), what variable is directly set by the clinician and remains constant despite changes in the patient's lung mechanics?

Minute ventilation
Peak inspiratory flow rate
Inspiratory pressure above PEEP (Correct answer)
Tidal volume delivered

Correct answer: Inspiratory pressure above PEEP

In PCV, the ventilator delivers gas until the set inspiratory pressure is reached and then maintains that pressure for the set inspiratory time. The pressure is constant regardless of lung compliance or resistance. Tidal volume, however, will vary — if lungs become stiffer, less volume is delivered at the same pressure. This is the fundamental difference from VCV.

Question 63: Under HIPAA's Security Rule, which control specifically addresses ensuring that ePHI transmitted over a network cannot be improperly modified without detection?

Audit controls
Person authentication
Transmission integrity (Correct answer)
Access control

Correct answer: Transmission integrity

Transmission integrity controls verify that ePHI is not altered or destroyed in an unauthorized manner during network transmission.

Question 64: What are the common sources of artifact in ECG monitoring and how can they be minimized?

Artifact is unavoidable
Artifact only comes from equipment malfunction
Common sources include muscle tremor, movement, poor electrode contact, 60Hz interference, and respiratory drift, minimized through proper skin preparation (Correct answer)
Only EMI causes artifact

Correct answer: Common sources include muscle tremor, movement, poor electrode contact, 60Hz interference, and respiratory drift, minimized through proper skin preparation

ECG artifact comes from multiple sources that can be minimized through proper electrode application and environmental controls.

Question 65: In a mechanical ventilator, what is the function of the PEEP (Positive End-Expiratory Pressure) valve?

To maintain positive pressure in the airways at the end of exhalation, preventing alveolar collapse (Correct answer)
To regulate oxygen concentration
To measure tidal volume
To trigger the next breath cycle

Correct answer: To maintain positive pressure in the airways at the end of exhalation, preventing alveolar collapse

The PEEP valve maintains positive pressure at end-exhalation, preventing alveoli from collapsing and improving oxygenation.

Question 66: Which of the following MOST accurately describes the hematocrit centrifuge's relative centrifugal force (RFC)?

3,000 RCF
10,000 RCF (Correct answer)
15,000 RCF
150,000 RCF

Correct answer: 10,000 RCF

Hematocrit centrifuges are designed to rapidly separate blood components, requiring a high relative centrifugal force (RCF) to efficiently pack red blood cells. An RCF of approximately 10,000-12,000 G (or RCF) is typically used for accurate hematocrit determination, making 10,000 RCF the most appropriate and common value among the choices for this application.

Question 67: When inspecting a sterile package before use, which finding would require the item to be reprocessed?

The outer wrap shows visible moisture damage (Correct answer)
The package seal is intact and unbroken
The chemical indicator has changed color correctly
The label shows a future expiration date

Correct answer: The outer wrap shows visible moisture damage

Moisture damage to sterile packaging compromises the barrier and can allow microbial contamination, requiring reprocessing of the item before use.

Question 68: What is the acceptable chassis leakage current limit for a Class I medical device under normal conditions per AAMI/IEC 60601-1?

5 mA
500 µA (Correct answer)
50 mA
5 µA

Correct answer: 500 µA

IEC 60601-1 limits chassis (enclosure) leakage to 500 µA under normal conditions to protect users and patients.

Question 69: What type of hypo/hyperthermia machine uses which thermoregulation technique?

Extracorporeal blood warming
Heating and cooling blankets (Correct answer)
Radiant heating and cooling
Ultraviolet heating

Correct answer: Heating and cooling blankets

Hypo/hyperthermia machines are used to precisely control a patient's body temperature. The most common and direct thermoregulation technique these machines employ involves circulating temperature-controlled fluid through specialized blankets or pads. These heating and cooling blankets are placed on or around the patient, allowing for efficient and controlled transfer of thermal energy to or from the patient's body.

Question 70: A syringe pump alarm indicates 'occlusion' repeatedly, but the IV line appears patent and free of kinks. What should be investigated?

The patient needs to be repositioned
The pump needs a firmware update
The syringe barrel may be binding, the plunger driver mechanism may be worn, or a downstream stopcock may be partially closed (Correct answer)
The pump needs to be replaced

Correct answer: The syringe barrel may be binding, the plunger driver mechanism may be worn, or a downstream stopcock may be partially closed

False occlusion alarms suggest excessive mechanical resistance from a binding plunger, worn mechanism, or partially closed stopcock.

Question 71: A hospital laboratory centrifuge vibrates excessively during operation. The MOST likely cause is:

An unbalanced load due to improperly paired or misplaced samples (Correct answer)
A failed tachometer sensor
Motor bearing wear causing rotor imbalance
Excessive ambient temperature in the lab

Correct answer: An unbalanced load due to improperly paired or misplaced samples

Centrifuges must have balanced loads; unequal or improperly positioned samples create centrifugal force imbalance causing severe vibration.

Question 72: According to Poiseuille's Law, if the radius of an IV catheter is halved, how does the maximum flow rate through it change (assuming all other variables remain constant)?

It decreases to one-eighth (12.5%)
It decreases by half (50%)
It decreases to one-quarter (25%)
It decreases to one-sixteenth (6.25%) (Correct answer)

Correct answer: It decreases to one-sixteenth (6.25%)

Poiseuille's Law states that flow rate (Q) is proportional to the fourth power of the radius (r⁴). Halving the radius reduces r⁴ by (1/2)⁴ = 1/16. Therefore, the flow rate drops to 1/16th (6.25%) of original. This is why catheter gauge has a dramatic effect on rapid fluid resuscitation — going from a 14g to an 18g catheter causes a large drop in max flow.

Question 73: A nurse reports that a patient's SpO2 monitor reads 98% while the patient appears cyanotic. Which troubleshooting step should be performed first?

Recalibrate the SpO2 module
Replace the entire monitor
Check probe placement and peripheral perfusion (Correct answer)
Measure ABG immediately and discard the monitor reading

Correct answer: Check probe placement and peripheral perfusion

Poor perfusion or improper probe placement are the most common causes of falsely high SpO2 readings before escalating to hardware replacement.

Question 74: When using a multimeter to measure AC voltage on a 120V circuit, the technician should set the range to:

A range equal to or above 120V to prevent meter damage (Correct answer)
The lowest range below 120V for best accuracy
DC voltage at 200V
Resistance mode to check the circuit first

Correct answer: A range equal to or above 120V to prevent meter damage

Always select a range at or above the expected voltage to prevent damage to the meter and ensure safe, accurate measurement.

Question 75: What parameter does capnography monitor and what is the normal end-tidal CO2 (EtCO2) range for a healthy adult?

Exhaled carbon dioxide concentration, 35-45 mmHg (Correct answer)
Inhaled oxygen concentration, 21%
Respiratory muscle effort, 10-20 cmH2O
Blood oxygen levels, 95-100%

Correct answer: Exhaled carbon dioxide concentration, 35-45 mmHg

Capnography monitors CO2 concentration in exhaled breath. Normal EtCO2 is 35-45 mmHg.

Question 76: A Safe Medical Devices Act (SMDA) requirement obligates hospitals to report device-related serious injuries to:

Both the FDA and the device manufacturer (Correct answer)
The Joint Commission only
The hospital's risk management department only
The state health department only

Correct answer: Both the FDA and the device manufacturer

Under the SMDA, user facilities must report serious injuries caused by medical devices to both the FDA and the manufacturer within 10 working days.

Question 77: What is the purpose of aeration after ethylene oxide (EtO) sterilization?

To remove toxic EtO residues from processed items (Correct answer)
To re-humidify the sterilized materials
To activate the sterilant residuals
To cool the sterilization chamber

Correct answer: To remove toxic EtO residues from processed items

EtO leaves toxic residues on sterilized items that can cause patient harm; aeration allows the residues to off-gas to safe levels before use.

Question 78: A DICOM workstation cannot retrieve images from the PACS server. After confirming network connectivity, the BMET should verify:

AE Title, IP address, and port configuration for both nodes (Correct answer)
Hard disk RAID redundancy status
Monitor calibration with a photometer
JPEG compression level settings

Correct answer: AE Title, IP address, and port configuration for both nodes

DICOM communication requires matching Application Entity (AE) Titles, correct IP addresses, and open TCP ports between devices.

Question 79: A BIOMED technician is testing an EtO (ethylene oxide) sterilizer. Which parameter is NOT critical to monitor during the EtO cycle?

Humidity
Gas concentration
Temperature
UV light exposure (Correct answer)

Correct answer: UV light exposure

EtO sterilization depends on gas concentration, temperature, humidity, and exposure time — UV light plays no role in this chemical sterilization process.

Question 80: What is the purpose of a sequential compression device (SCD) and what does a biomedical technician verify?

Compresses surgical instruments
Provides chest compressions during CPR
Compresses IV fluid bags
Applies intermittent pneumatic compression to legs to prevent deep vein thrombosis (Correct answer)

Correct answer: Applies intermittent pneumatic compression to legs to prevent deep vein thrombosis

SCDs apply sequential pneumatic pressure to leg sleeves to promote venous blood return and prevent DVT.

Question 81: A BMET is performing a preventive maintenance inspection on a pneumatic surgical tourniquet. Which of the following is the MOST critical safety verification?

Ensuring the audible alarm is louder than 85 decibels
Checking the integrity of the power cord and plug
Confirming the unit's battery can hold a charge for at least 4 hours
Verifying the accuracy of the pressure display and its ability to maintain a set pressure (Correct answer)

Correct answer: Verifying the accuracy of the pressure display and its ability to maintain a set pressure

The most critical function of a pneumatic tourniquet is to apply and maintain a precise, stable pressure to occlude blood flow safely. Verifying the accuracy of the pressure transducer and ensuring the system can hold a set pressure without significant leaks are paramount to preventing patient injury, such as nerve damage from over-pressurization or loss of the surgical field from under-pressurization.

Question 82: Which safety system is specifically designed to prevent the accidental connection of the wrong gas-specific flowmeter or hose to a medical gas wall outlet?

Pin Index Safety System (PISS)
Color Coding System
Compressed Gas Association (CGA) fitting
Diameter Index Safety System (DISS) (Correct answer)

Correct answer: Diameter Index Safety System (DISS)

The Diameter Index Safety System (DISS) uses non-interchangeable, gas-specific threaded connections on wall outlets and equipment to prevent misconnections. Each gas service has a unique set of diameters on the connector body and nipple, making it physically impossible to connect equipment for one gas to the outlet of another. PISS is used for small gas cylinders, not wall outlets.

Question 83: Which blood vessel carries deoxygenated blood from the heart to the lungs?

Pulmonary artery (Correct answer)
Aorta
Superior vena cava
Pulmonary vein

Correct answer: Pulmonary artery

The pulmonary artery carries deoxygenated blood from the right ventricle to the lungs for gas exchange.

Question 84: The sinoatrial (SA) node is located in which chamber of the heart?

Right ventricle
Right atrium (Correct answer)
Left ventricle
Left atrium

Correct answer: Right atrium

The SA node, often called the heart's natural pacemaker, is located in the upper wall of the right atrium near the superior vena cava opening.

Question 85: Which type of surgical laser is highly absorbed by water, making it extremely effective for precise soft-tissue cutting and vaporization with minimal collateral thermal damage?

KTP (Potassium Titanyl Phosphate)
Nd:YAG (Neodymium-doped Yttrium Aluminum Garnet)
Argon
CO2 (Carbon Dioxide) (Correct answer)

Correct answer: CO2 (Carbon Dioxide)

The CO2 laser operates at a wavelength (typically 10,600 nm) in the far-infrared spectrum that is strongly absorbed by water, the primary component of soft tissue. This high absorption allows the laser to vaporize tissue very precisely at the point of contact, with a shallow depth of penetration and minimal spread of heat to surrounding areas.

Question 86: Which parameter is checked during an acceptance test for a defibrillator to verify energy delivery accuracy?

Delivered energy measured with a calibrated defibrillator analyzer (Correct answer)
Battery voltage at rest
Electrode impedance in open air
Charge time to maximum energy

Correct answer: Delivered energy measured with a calibrated defibrillator analyzer

A calibrated defibrillator analyzer measures actual delivered energy into a known load, verifying the device delivers the energy it displays.

Question 87: What does HIPAA require regarding the transmission of electronic Protected Health Information (ePHI) over a network?

ePHI must be stored on local drives only
ePHI must be encrypted during transmission using appropriate safeguards (Correct answer)
ePHI must only be sent via fax
ePHI can be sent in plaintext if the network is internal

Correct answer: ePHI must be encrypted during transmission using appropriate safeguards

HIPAA's Security Rule requires that ePHI transmitted over networks be protected through encryption and other technical safeguards.

Question 88: What is the primary function of the alveoli in the lungs?

Gas exchange between air and blood (Correct answer)
Producing surfactant only
Warming inhaled air
Filtering inhaled particles

Correct answer: Gas exchange between air and blood

Alveoli are tiny air sacs in the lungs where the exchange of oxygen and carbon dioxide between inhaled air and pulmonary capillary blood occurs.

Question 89: A harmonic scalpel is a surgical instrument that cuts and coagulates tissue. What is the underlying physical principle it uses to achieve this effect?

High-frequency ultrasonic vibration (Correct answer)
Focused high-intensity laser energy
Radiofrequency electrical current
Pressurized argon gas plasma

Correct answer: High-frequency ultrasonic vibration

A harmonic scalpel uses a piezoelectric transducer in the handpiece to convert electrical energy into high-frequency (typically 55,500 Hz) ultrasonic mechanical vibrations. This vibration is transferred to the blade, which denatures proteins and creates a coagulum to seal vessels while simultaneously cutting tissue with minimal thermal spread.

Question 90: A pulse oximeter reads 98% SpO2 but the patient appears cyanotic. Which condition MOST likely explains this discrepancy?

Carbon monoxide poisoning causing carboxyhemoglobin (Correct answer)
Hypothermia reducing peripheral perfusion
Anemia with normal oxygen saturation
Motion artifact from patient tremors

Correct answer: Carbon monoxide poisoning causing carboxyhemoglobin

Pulse oximetry cannot distinguish carboxyhemoglobin from oxyhemoglobin, so CO poisoning produces falsely elevated SpO2 readings despite true hypoxia.

Question 91: During PM on a clinical centrifuge, a BMET notices excessive vibration during a spin cycle. What should be checked FIRST?

Speed control potentiometer calibration
Timer relay contacts
Carbon brushes on the drive motor
Rotor balance and proper symmetrical tube loading (Correct answer)

Correct answer: Rotor balance and proper symmetrical tube loading

Vibration in a centrifuge is most commonly caused by imbalanced loads — mismatched tube weights or asymmetric placement in the rotor. An imbalanced rotor can cause catastrophic rotor failure. Motor brushes cause speed issues, not vibration, and the speed control and timer are not mechanical vibration sources.

Question 92: Dry heat sterilization at 160°C requires what minimum exposure time to achieve sterilization?

30 minutes
120 minutes (Correct answer)
60 minutes
180 minutes

Correct answer: 120 minutes

Dry heat sterilization at 160°C (320°F) requires a minimum of 120 minutes to kill all microorganisms, as dry heat is less efficient than moist heat.

Question 93: A surgical electrosurgical unit (ESU) causes interference on a nearby patient monitor. The FIRST corrective action should be:

Replace the patient monitor
Check and ensure proper placement and contact of the ESU dispersive electrode (Correct answer)
Move the patient monitor to a different room
Install a new ESU with digital output

Correct answer: Check and ensure proper placement and contact of the ESU dispersive electrode

Improper dispersive electrode placement causes high-frequency current to seek alternate paths, creating interference in nearby monitoring equipment.

Question 94: Which OSHA standard most directly governs healthcare worker safety when handling ethylene oxide sterilizers?

29 CFR 1910.1030 (Bloodborne Pathogens)
29 CFR 1910.1047 (Ethylene Oxide Standard) (Correct answer)
29 CFR 1910.1200 (Hazard Communication)
29 CFR 1910.134 (Respiratory Protection)

Correct answer: 29 CFR 1910.1047 (Ethylene Oxide Standard)

OSHA 29 CFR 1910.1047 specifically regulates occupational exposure to ethylene oxide, including permissible exposure limits, monitoring, and worker protections.

Question 95: When troubleshooting a pulse oximeter that is giving an erratic SpO2 reading, the CBET should understand that the device's measurement principle is based on the absorption of light by what substance in the blood?

White blood cells
Plasma
Platelets
Hemoglobin (Correct answer)

Correct answer: Hemoglobin

Pulse oximeters work by passing red and infrared light through a capillary bed and measuring the differential absorption. The amount of light absorbed is dependent on the oxygenation level of hemoglobin, the protein in red blood cells that carries oxygen.

Question 96: What is a telemetry monitoring system and how does it differ from bedside monitoring?

Telemetry uses wired connections
Telemetry uses portable wireless transmitters on ambulatory patients, sending ECG data to a central station (Correct answer)
Telemetry is more accurate
Telemetry only works in operating rooms

Correct answer: Telemetry uses portable wireless transmitters on ambulatory patients, sending ECG data to a central station

Telemetry uses small portable wireless transmitters enabling continuous monitoring while patients walk around.

Question 97: What information is typically recorded in a PM completion report?

Nurse staffing ratios
Date, technician ID, tests performed, results, and any parts replaced (Correct answer)
Patient diagnosis codes
Hospital revenue figures

Correct answer: Date, technician ID, tests performed, results, and any parts replaced

PM documentation creates an auditable service record demonstrating the device was inspected, tested, and found safe on a specific date.

Question 98: What special precautions must be taken when working on medical gas pipelines during construction in an occupied hospital?

Just closing zone valves is sufficient
Only color verification is needed
Pipeline isolation, gas verification at every affected outlet, infection control measures, and NFPA 99 compliance (Correct answer)
Standard construction practices are sufficient

Correct answer: Pipeline isolation, gas verification at every affected outlet, infection control measures, and NFPA 99 compliance

Construction near gas pipelines requires comprehensive safety measures including ICRA, clinical notification, and verification at every outlet.

Question 99: A BMET is tasked with troubleshooting an intermittent "No Signal" error on a single patient monitor connected to a large central monitoring network. The problem occurs randomly. Which of the following represents the MOST effective initial troubleshooting approach?

Immediately replace the patient monitor with a new one.
Re-terminate the network connections at the wall plate and the back of the monitor.
Request the hospital's IT department to reboot the central network switch for that floor.
Systematically swap components one at a time with known good ones, starting with the easiest to replace. (Correct answer)

Correct answer: Systematically swap components one at a time with known good ones, starting with the easiest to replace.

For intermittent problems, systematically swapping components is a highly effective troubleshooting technique. Starting with the simplest and most common failure points, such as the network patch cable, then the monitor itself, allows the technician to isolate the faulty element without making assumptions or performing unnecessarily disruptive actions like rebooting a network switch.

Question 100: A nurse reports that an ECG waveform on a patient monitor shows a thick, fuzzy baseline, consistent across all leads. The patient is calm and still. Which of the following is the MOST likely cause of this 60 Hz interference artifact?

A detached right leg (reference) electrode.
Patient shivering or muscle tremors.
Improper grounding of the monitor or another nearby electrical device. (Correct answer)
The ECG gain setting being too high.

Correct answer: Improper grounding of the monitor or another nearby electrical device.

A thick, regular, fuzzy baseline is characteristic of 60 Hz (or 50 Hz in some regions) AC electrical interference. This noise is introduced from nearby power lines or equipment and is most often caused by improper grounding of the patient monitor or another electrical device in the patient's vicinity. Patient tremors cause irregular, jagged artifacts, while a detached reference lead often results in a wandering baseline or complete loss of signal. High gain would amplify the existing signal and noise but is not the root cause of the 60 Hz interference itself.

Question 101: Which document typically defines the required PM interval for a medical device in a US hospital?

Manufacturer's service manual (Correct answer)
State pharmacy license
Hospital billing records
Patient intake form

Correct answer: Manufacturer's service manual

The manufacturer's service manual specifies recommended PM intervals and procedures that biomed departments use to build their maintenance schedules.

Question 102: In which one of the following muscle types are the filaments disorganized?

Skeletal
Cardiac
Rough
Smooth (Correct answer)

Correct answer: Smooth

Smooth muscle cells lack the highly organized sarcomeres and striations characteristic of skeletal and cardiac muscle. Their actin and myosin filaments are arranged in a more haphazard, crisscrossing pattern throughout the cytoplasm. This less organized arrangement allows smooth muscle to contract and stretch over a wider range of lengths, which is crucial for its function in organs like the digestive tract and blood vessels.

Question 103: What is the primary function of an isolation transformer in medical equipment used in a hospital operating room?

To provide a grounded power source for all connected equipment.
To increase the voltage for high-power devices.
To create an ungrounded electrical system that reduces the risk of macroshock from a single fault. (Correct answer)
To convert AC power to DC power for sensitive electronics.

Correct answer: To create an ungrounded electrical system that reduces the risk of macroshock from a single fault.

Isolation transformers are crucial for electrical safety in critical care areas like operating rooms. They create a 'floating' or ungrounded secondary circuit. In a standard grounded system, touching a single live wire while grounded can cause a severe shock. With an isolated system, touching one of the secondary conductors while grounded will not complete a circuit, thus preventing a macroshock. This significantly enhances patient and staff safety.

Question 104: Which organ is primarily responsible for filtering blood and producing urine in the human body?

Spleen
Pancreas
Liver
Kidney (Correct answer)

Correct answer: Kidney

The kidneys filter blood to remove waste products and excess fluids, producing urine as a byproduct of this filtration process.

Question 105: In a hemodialysis machine, the dialysate flow direction relative to blood flow is typically:

Intermittent, alternating direction every five minutes
Co-current, to prevent pressure differentials across the membrane
Perpendicular, to promote ultrafiltration only
Countercurrent, to maximize the concentration gradient for diffusion across the dialyzer membrane (Correct answer)

Correct answer: Countercurrent, to maximize the concentration gradient for diffusion across the dialyzer membrane

Countercurrent flow maintains a favorable concentration gradient along the entire length of the dialyzer, maximizing solute clearance.

Question 106: A technician is performing PM on a patient-controlled analgesia (PCA) pump and must verify occlusion alarm response. The correct test method is:

Increase the infusion rate beyond maximum and observe the display
Disconnect the AC power and measure battery backup alarm delay
Block the outlet tubing and measure elapsed time to alarm activation (Correct answer)
Introduce air into the IV line and monitor the air-in-line sensor

Correct answer: Block the outlet tubing and measure elapsed time to alarm activation

Occlusion alarm testing requires physically blocking fluid flow at the outlet and confirming the pump alarms within the manufacturer's specified time limit.

Question 107: A new infusion pump is delivered to the hospital. The specifications state it uses a peristaltic mechanism. How does this type of pump move fluid through the IV tubing?

By creating a pressure differential with a vacuum system.
By using rotating rollers or 'fingers' to sequentially compress the tubing. (Correct answer)
By using a motor to precisely advance a plunger within a syringe.
By using gravity and controlling the flow with a simple roller clamp.

Correct answer: By using rotating rollers or 'fingers' to sequentially compress the tubing.

Peristaltic pumps function by using a set of rotating rollers that press against a flexible tube. As the rollers move along the tube, they create a pocket of fluid that is pushed forward, mimicking the biological process of peristalsis. This mechanism allows for controlled fluid delivery without the pump's components directly contacting the fluid.

Question 108: A BMET is performing a PM on an infusion pump. Which test is most critical for patient safety?

Speaker volume check
Label legibility inspection
Flow rate accuracy test (Correct answer)
Keypad illumination check

Correct answer: Flow rate accuracy test

Flow rate accuracy directly affects drug dosing; an out-of-tolerance pump can deliver under- or over-doses with life-threatening consequences.

Question 109: Which type of joint allows the greatest range of motion in the human body?

Pivot joint
Hinge joint
Ball-and-socket joint (Correct answer)
Saddle joint

Correct answer: Ball-and-socket joint

Ball-and-socket joints, such as the hip and shoulder, allow movement in all directions including rotation, providing the greatest range of motion.

Question 110: A patient reports receiving a mild tingling sensation when touching the bed rail while connected to a patient monitor. No alarm has triggered. What is the appropriate immediate action?

Tell the patient it is normal static electricity
Apply hand lotion to the patient's skin
Increase the monitor alarm volume
Immediately disconnect the patient from the monitor, remove the device from service, and perform electrical safety testing (Correct answer)

Correct answer: Immediately disconnect the patient from the monitor, remove the device from service, and perform electrical safety testing

A tingling sensation indicates stray electrical current flowing through the patient, which is a potentially dangerous leakage current situation.

Question 111: What is the primary safety concern for BMETs working on MRI equipment?

Laser eye injury
High voltage electric shock only
Radioactive contamination
Extremely strong static magnetic field attracting ferromagnetic objects (Correct answer)

Correct answer: Extremely strong static magnetic field attracting ferromagnetic objects

MRI scanners operate with static fields up to 3 T or higher; ferromagnetic tools or implants can become dangerous projectiles near the bore.

Question 112: What does a medical gas alarm panel monitor and how should alarms be responded to?

Individual cylinder levels for automatic reordering
Pipeline pressure, reserve supply status, and system conditions, requiring immediate investigation (Correct answer)
Room temperature requiring HVAC adjustment
Gas purity requiring filter replacement

Correct answer: Pipeline pressure, reserve supply status, and system conditions, requiring immediate investigation

Medical gas alarm panels monitor pipeline pressures, reserve supply status, and operating conditions.

Question 113: An infusion pump alarms 'upstream occlusion' but the tubing appears clear. What should the BMET check next?

Battery level of the pump
Software version of the pump firmware
Closed roller clamp or kinked tubing upstream of the pump (Correct answer)
IV bag height relative to the patient

Correct answer: Closed roller clamp or kinked tubing upstream of the pump

A closed clamp or subtle kink upstream of the pump head is the most frequent cause of upstream occlusion alarms when visible tubing appears unobstructed.

Question 114: Which standard specifies that the maximum allowable leakage current for chassis-to-ground on patient care equipment (normal condition) is 300 µA?

IEC 62353
NFPA 70
ANSI/AAMI ES60601-1 (Correct answer)
OSHA 29 CFR 1910

Correct answer: ANSI/AAMI ES60601-1

ANSI/AAMI ES60601-1 (derived from IEC 60601-1) specifies chassis leakage current limits for medical electrical equipment, with 300 µA as the normal-condition limit for patient care equipment.

Question 115: What principle does an ultrasound imaging system use to create images of internal body structures?

Infrared thermal detection
Magnetic resonance of hydrogen atoms
Piezoelectric transducer emitting and receiving high-frequency sound waves (Correct answer)
Ionizing radiation absorption

Correct answer: Piezoelectric transducer emitting and receiving high-frequency sound waves

Ultrasound uses piezoelectric transducers to emit high-frequency sound waves and detect reflected echoes to create real-time images.

Question 116: What is the primary security concern when medical devices run outdated or unpatched operating systems?

Incompatibility with newer printers
Known vulnerabilities that can be exploited by malware or attackers (Correct answer)
Slower boot times
Higher power consumption

Correct answer: Known vulnerabilities that can be exploited by malware or attackers

Unpatched devices contain known security vulnerabilities that can be exploited by malware or attackers to compromise patient data or disrupt device operation.

Question 117: What is the function of a fetal monitor and what two primary parameters does it continuously measure?

Maternal blood pressure and fetal weight
Fetal heart rate (FHR) and uterine contraction activity (tocometry) (Correct answer)
Maternal ECG and fetal movement
Fetal blood oxygen and respiratory rate

Correct answer: Fetal heart rate (FHR) and uterine contraction activity (tocometry)

A fetal monitor (cardiotocograph) measures fetal heart rate using Doppler ultrasound and uterine contractions using a tocodynamometer.

Question 118: What is the correct term for the process of reducing microbial contamination to a safe level without achieving sterility?

Decontamination
Disinfection (Correct answer)
Sterilization
Antisepsis

Correct answer: Disinfection

Disinfection reduces the number of viable microorganisms to a level considered safe for handling but does not necessarily eliminate all spores.

Question 119: A BMET is troubleshooting a networked medical device that is failing to transmit patient data to the Electronic Health Record (EHR). The device has a valid IP address and can ping other devices on the same subnet. Which of the following is the MOST likely cause of the issue?

A misconfigured subnet mask
Incorrect VLAN assignment (Correct answer)
A faulty Ethernet cable
An IP address conflict

Correct answer: Incorrect VLAN assignment

A Virtual LAN (VLAN) is used to segment a network. If the medical device is on a different VLAN than the EHR server, it will not be able to communicate, even with correct IP settings for its own subnet. Since the device can ping other local devices, the cable and basic IP configuration are likely correct.

Question 120: What is the MAUDE database and how is it used?

A hospital inventory system
A device purchasing database
A manufacturer warranty system
An FDA database of adverse event reports used to identify device safety trends and problems (Correct answer)

Correct answer: An FDA database of adverse event reports used to identify device safety trends and problems

MAUDE is a publicly searchable FDA database containing medical device adverse event reports.

Question 121: What is the primary purpose of a surgical tourniquet system and what safety features must be verified?

To measure blood pressure during surgery
To restrict blood flow to a limb by applying controlled pressure, with pressure and time monitoring for safety (Correct answer)
To deliver anesthetic agents
To warm the patient

Correct answer: To restrict blood flow to a limb by applying controlled pressure, with pressure and time monitoring for safety

Surgical tourniquets restrict blood flow using pneumatic cuffs, with critical safety features including accurate pressure regulation and time monitoring.

Question 122: In electrosurgical units (ESU), the return electrode (dispersive pad) functions by:

Distributing current over a large surface area to minimize current density at the patient return site (Correct answer)
Grounding the patient to earth to prevent shock
Increasing the frequency of current to improve cutting precision
Concentrating current to coagulate tissue at the return site

Correct answer: Distributing current over a large surface area to minimize current density at the patient return site

The large area of the dispersive pad spreads current so densely is too low to heat tissue, preventing burns at the return site.

Question 123: In a pulse oximeter, which physiological principle is used to differentiate oxygenated from deoxygenated hemoglobin?

Differential light absorption at two wavelengths (660 nm and 940 nm) (Correct answer)
Measurement of blood pressure waveform morphology
Impedance plethysmography across the finger
Detection of CO2 partial pressure via infrared spectroscopy

Correct answer: Differential light absorption at two wavelengths (660 nm and 940 nm)

Pulse oximeters exploit the fact that oxyhemoglobin and deoxyhemoglobin absorb red (660 nm) and infrared (940 nm) light at different ratios.

Question 124: During arthroscopic surgery, the fluid pump pressure is set to 60 mmHg but the surgeon reports poor visualization. What should the BMET check FIRST?

Pump motor speed calibration
Integrity of the arthroscope sheath seals and outflow cannula patency (Correct answer)
Fluid bag temperature
Light source cable connection

Correct answer: Integrity of the arthroscope sheath seals and outflow cannula patency

Leaking sheath seals or blocked outflow cannulas prevent adequate joint distension, causing poor visualization despite correct pump settings.

Question 125: What is the maximum allowable chassis leakage current for a patient-connected device in a general care area according to NFPA 99?

500 µA
100 µA (Correct answer)
10 µA
300 µA

Correct answer: 100 µA

NFPA 99 limits chassis leakage current to 100 µA for patient-connected equipment in general care areas.

Question 126: What is the primary hazard of using a cylinder of compressed oxygen in an area with oil-contaminated fittings?

Increase in pipeline dew point
Back-pressure damage to the regulator
Risk of fire or explosion due to oxygen-enriched ignition of oil (Correct answer)
Rapid depletion of oxygen supply

Correct answer: Risk of fire or explosion due to oxygen-enriched ignition of oil

Oil in contact with high-pressure oxygen can ignite spontaneously, creating a severe fire or explosion hazard; all oxygen equipment must be oil-free.

Question 127: During MRI QA, the BMET measures a phantom image and finds the signal-to-noise ratio (SNR) has dropped 20% from baseline. The most likely cause is:

RF coil damage or poor coupling (Correct answer)
Gradient amplifier overheating
Incorrect TR parameter
Incorrect slice thickness setting

Correct answer: RF coil damage or poor coupling

A damaged or poorly coupled RF coil reduces the received signal strength, directly decreasing SNR.

Question 128: What does the term 'duty cycle' refer to in the context of an electrosurgical unit?

The ratio of active current delivery time to total cycle time, which differentiates cutting from coagulation modes (Correct answer)
The percentage of time the device is powered on per day
The percentage of power output relative to maximum
The number of procedures before maintenance

Correct answer: The ratio of active current delivery time to total cycle time, which differentiates cutting from coagulation modes

CUT mode uses continuous waveform (100% duty cycle) for tissue vaporization; COAGULATION uses intermittent waveform (6% duty cycle) for protein denaturation.

Question 129: A new enteral feeding pump is placed into use, but it is soon sent to Biomed for repair. According to the complaint, it was operating normally until it started displaying a persistent low-flow error. Which of the following symptoms would NOT set off the alarm?

Excessive ambient light by the feeding set detector (Correct answer)
Feeding solution coating drip chamber walls
Kinked or clamped tubing upstream of the pump
A dislodged drip chamber

Correct answer: Excessive ambient light by the feeding set detector

Enteral feeding pumps often use optical sensors to detect fluid flow, such as a drip chamber sensor. Kinked tubing, a dislodged drip chamber, or feeding solution coating the drip chamber walls would directly impede flow or interfere with the sensor's ability to detect flow, thus triggering a low-flow alarm. Excessive ambient light, however, is generally unlikely to directly cause a low-flow error, as these sensors are typically designed to filter out ambient light or use specific light frequencies.

Question 130: How should a biomedical technician verify that a repaired medical gas outlet is delivering the correct gas before returning it to service?

Ask a nurse to smell the gas
Connect a flowmeter and check the reading
Use a gas-specific analyzer to verify gas identity, then test flow rate and pressure (Correct answer)
Check the color coding only

Correct answer: Use a gas-specific analyzer to verify gas identity, then test flow rate and pressure

A gas-specific analyzer must be used to positively verify the gas identity at the outlet.

Question 131: Which imaging modality uses radiofrequency pulses and a strong magnetic field rather than ionizing radiation?

Fluoroscopy
Computed Tomography (CT)
Bone densitometry (DEXA)
MRI (Magnetic Resonance Imaging) (Correct answer)

Correct answer: MRI (Magnetic Resonance Imaging)

MRI aligns hydrogen protons with a strong magnetic field then uses RF pulses to disturb and detect their relaxation, producing images without ionizing radiation.

Question 132: What safety feature prevents a patient from receiving an uncontrolled free flow of IV fluid if the tubing is removed from an infusion pump?

The filter in the tubing
The drip chamber
The roller clamp
Anti-free-flow clamp mechanism built into the pump door or tubing set (Correct answer)

Correct answer: Anti-free-flow clamp mechanism built into the pump door or tubing set

The anti-free-flow mechanism automatically occludes the tubing when removed from the pump, preventing uncontrolled fluid delivery.

Question 133: When comparing mainstream and sidestream capnography, which of the following is a primary advantage of the mainstream method?

It is less susceptible to being clogged by patient secretions.
It uses a disposable sampling line, reducing cleaning requirements.
It provides a faster response time with a more distinct waveform. (Correct answer)
It does not add any weight or bulk to the patient's breathing circuit.

Correct answer: It provides a faster response time with a more distinct waveform.

Mainstream capnography places the CO2 sensor directly in the patient's breathing circuit, allowing for instantaneous measurement of exhaled gas. This results in a faster response time and a sharper, more accurate waveform compared to sidestream, which must pull a gas sample through a tube to a remote sensor, introducing a time delay. The disadvantages of mainstream are its added weight at the airway and potential for clogging, while the disposable sampling line is a feature of sidestream.

Question 134: What is the purpose of a ground wire (green or green/yellow) in a medical device power cord?

To supply backup power during outages
To provide a low-impedance fault current path to trip the circuit breaker (Correct answer)
To carry the return current during normal operation
To filter electromagnetic interference

Correct answer: To provide a low-impedance fault current path to trip the circuit breaker

The ground wire provides a low-impedance path for fault current to flow back to the source, tripping the circuit breaker quickly and protecting patients and staff.

Question 135: A surgeon reports that the electrosurgical unit (ESU) is not cutting effectively despite being set to the usual power level. The return electrode pad is properly applied. What should you check?

The room temperature setting
The operating table height
The active electrode tip for damage, carbon buildup, or improper connection (Correct answer)
The anesthesia machine settings

Correct answer: The active electrode tip for damage, carbon buildup, or improper connection

Reduced ESU cutting effectiveness typically indicates carbon buildup on the electrode tip, a damaged tip, or a poor connection.

Question 136: A CBET is working in a newly constructed critical care unit. According to the risk-based approach of NFPA 99, systems and equipment whose failure is likely to cause major injury or death to patients or caregivers would be designated as which category?

Category 4
Category 1 (Correct answer)
Category A
Category 2

Correct answer: Category 1

NFPA 99 uses a risk-based classification system. Category 1 is assigned to systems and equipment where failure is likely to cause major injury or death. This category requires the most stringent design and testing standards to ensure reliability and safety.

Question 137: A BMET is testing a phototherapy unit used to treat neonatal hyperbilirubinemia (jaundice). Which characteristic of the light output is MOST critical to measure during PM?

Total luminous flux (lumens) across the visible spectrum
Color temperature in Kelvins
Irradiance (spectral power) in the 430–490 nm (blue) wavelength range at the treatment surface (Correct answer)
Ultraviolet output above 380 nm to ensure bactericidal effect

Correct answer: Irradiance (spectral power) in the 430–490 nm (blue) wavelength range at the treatment surface

Phototherapy for neonatal jaundice works by photoisomerizing bilirubin in the skin into water-soluble isomers that can be excreted. This photo-reaction is driven specifically by blue light in the 430–490 nm range. The therapeutic dose is measured as irradiance (µW/cm²/nm) in this band at the skin surface. A lamp that produces sufficient total lumens but has degraded blue output will be ineffective, so spectral irradiance in the blue band is the critical PM measurement.

Question 138: A biomedical technician must ensure an ECG machine's patient lead leakage current does not exceed which limit for a CF-type device per IEC 60601-1?

500 µA under normal conditions
50 µA under normal conditions
100 µA under normal conditions
10 µA under normal conditions (Correct answer)

Correct answer: 10 µA under normal conditions

For CF (cardiac floating) applied parts, IEC 60601-1 limits patient leakage current to 10 µA under normal conditions due to direct cardiac risk.

Question 139: A PM checklist for a defibrillator requires verifying delivered energy at 200 J. The analyzer reads 188 J. Per AAMI standards, this result is:

Acceptable; within the ±15% tolerance allowed (Correct answer)
Unacceptable; only ±1% tolerance is permitted
Unacceptable; defibrillators must deliver within ±5 J
Acceptable; any reading above 150 J passes

Correct answer: Acceptable; within the ±15% tolerance allowed

AAMI DF80 allows defibrillator delivered energy to be within ±15% of the selected setting; 188 J is a 6% deviation and therefore acceptable.

Question 140: According to NFPA 99, what is the maximum allowable chassis leakage current for a new, cord-connected, non-patient care-related electrical appliance used within the patient care vicinity?

300 microamps
100 microamps
10 milliamps
500 microamps (Correct answer)

Correct answer: 500 microamps

NFPA 99 (2005 edition) states that the chassis leakage current for facility-owned, non-patient care-related appliances, such as housekeeping or maintenance equipment, shall not exceed 500 microamps when used in the patient care vicinity. The limit for patient-care related appliances is generally lower, at 300 microamps.

Question 141: What are the biomedical technician's responsibilities regarding infection control when servicing medical equipment?

Technicians are exempt
Follow standard precautions, request decontamination, use PPE, and prevent cross-contamination between devices (Correct answer)
Only hand washing is required
Only nursing staff's responsibility

Correct answer: Follow standard precautions, request decontamination, use PPE, and prevent cross-contamination between devices

Technicians must follow standard precautions, ensure decontamination, use appropriate PPE, and prevent cross-contamination.

Question 142: Which type of transformer configuration is used in medical-grade isolated power systems to prevent shock hazard?

Step-down transformer
Autotransformer
Toroidal transformer
Isolation transformer (Correct answer)

Correct answer: Isolation transformer

Isolation transformers break the galvanic connection between utility power and the patient care area, preventing ground-fault shock.

Question 143: Which sterilization method is CONTRAINDICATED for sterilizing powered surgical instruments with sealed electronics?

Hydrogen peroxide gas plasma
Steam autoclave at 134°C (Correct answer)
Ethylene oxide (EtO)
Low-temperature vaporized hydrogen peroxide

Correct answer: Steam autoclave at 134°C

High-temperature steam autoclaving can damage sealed electronics, batteries, and sensitive components in powered surgical instruments.

Question 144: What is the difference between invasive and non-invasive blood pressure monitoring, and when is invasive monitoring preferred?

There is no clinical difference
Invasive is less accurate but faster
Invasive uses an arterial catheter and transducer for continuous beat-to-beat monitoring in hemodynamically unstable patients (Correct answer)
Invasive uses a larger cuff

Correct answer: Invasive uses an arterial catheter and transducer for continuous beat-to-beat monitoring in hemodynamically unstable patients

Invasive monitoring uses an arterial catheter connected to a pressure transducer for continuous real-time measurement.

Question 145: During a robotic-assisted surgery, a robotic arm instrument fails to respond to surgeon commands. The FIRST step a BMET should take is:

Reboot the entire robotic console
Notify the surgeon to switch to manual technique
Replace the robotic arm assembly
Check the instrument-arm communication cable connections (Correct answer)

Correct answer: Check the instrument-arm communication cable connections

Verifying cable connections is the first logical troubleshooting step before escalating to more invasive actions like rebooting or replacing components.

Question 146: A biomedical equipment technician is performing an electrical safety inspection on a portable medical device. The resistance measurement between the ground pin of the attachment plug and the device's metal chassis should be less than what value to be considered safe?

5.0 ohms
0.5 ohms (Correct answer)
0.1 ohms
1.0 ohm

Correct answer: 0.5 ohms

To ensure a reliable path to earth ground in case of a fault, the resistance between the chassis and the ground pin of the power cord must be very low. According to NFPA 99, this resistance must be less than 0.5 ohms. A low-resistance ground path is critical for shunting fault currents safely to the ground, preventing the chassis from becoming energized.

Question 147: Which part of the nervous system controls involuntary functions such as heart rate and digestion?

Somatic nervous system
Central nervous system
Peripheral motor system
Autonomic nervous system (Correct answer)

Correct answer: Autonomic nervous system

The autonomic nervous system (ANS) controls involuntary body functions including heart rate, blood pressure, digestion, and respiratory rate.

Question 148: A neonatal ICU monitor alarm activates for a SpO2 reading of 80%. The BMET verifies equipment function is normal. What physiological artifact is LEAST likely responsible?

Elevated fetal hemoglobin concentration (Correct answer)
Motion artifact from infant movement
Peripheral vasoconstriction reducing perfusion
Probe placed on an edematous extremity

Correct answer: Elevated fetal hemoglobin concentration

Fetal hemoglobin (HbF) has similar optical absorption properties to adult hemoglobin at standard oximetry wavelengths and does not significantly cause inaccurate SpO2 readings.

Question 149: What does the term 'equipotential grounding' mean in the context of a hospital operating room?

All equipment uses the same voltage level
All conductive surfaces within patient reach are connected to a common ground point (Correct answer)
All ground wires are the same length
All equipment is powered from the same circuit breaker

Correct answer: All conductive surfaces within patient reach are connected to a common ground point

Equipotential grounding ensures that all conductive surfaces within patient reach are bonded to a single ground reference point, eliminating dangerous potential differences.

Question 150: Which cranial nerve is primarily responsible for carrying parasympathetic fibers to the heart and abdominal organs?

Hypoglossal nerve (CN XII)
Vagus nerve (CN X) (Correct answer)
Trigeminal nerve (CN V)
Glossopharyngeal nerve (CN IX)

Correct answer: Vagus nerve (CN X)

The vagus nerve (CN X) provides the major parasympathetic innervation to the heart, lungs, and most abdominal organs.

Question 151: A surgical laser system shows reduced beam power output despite the laser being fully charged. What is the most likely cause?

Depleted cooling water reservoir
Damaged fiber optic delivery cable (Correct answer)
Faulty footswitch
Incorrect voltage supply

Correct answer: Damaged fiber optic delivery cable

Damaged or bent fiber optic delivery cables are a common cause of reduced laser power output due to increased transmission losses.

Question 152: What type of radiation does a conventional X-ray machine produce?

Ionizing electromagnetic radiation (X-rays) (Correct answer)
Non-ionizing infrared radiation
Gamma radiation from isotopes
Ultrasonic sound waves

Correct answer: Ionizing electromagnetic radiation (X-rays)

X-ray tubes produce ionizing electromagnetic radiation by accelerating electrons into a tungsten anode, emitting photons in the X-ray spectrum.

Question 153: A newly installed, permanently wired (fixed) piece of medical imaging equipment is being tested. Before any grounds are connected, what is the maximum allowable ground leakage current according to NFPA 99 standards?

1 milliamp
500 microamps
5 milliamps
10 milliamps (Correct answer)

Correct answer: 10 milliamps

For permanently wired equipment, NFPA 99 allows for a higher leakage current limit compared to portable devices. The ground leakage current, tested before the permanent ground is connected, must not exceed 10.0 mA. This test is typically performed on new installations.

Question 154: How does a harmonic (ultrasonic) surgical device differ from traditional electrosurgery?

It uses mechanical vibration at 55,500 Hz to cut and coagulate with lower temperature and less thermal damage (Correct answer)
Same mechanism at lower power
It uses high-pressure water
It uses heat from an external source

Correct answer: It uses mechanical vibration at 55,500 Hz to cut and coagulate with lower temperature and less thermal damage

Harmonic scalpels use ultrasonic vibration creating tissue effects at 50-100 degrees C versus 150-400 degrees C for electrosurgery.

Question 155: Which unit describes the absorbed radiation dose in diagnostic imaging?

Gray (Gy) (Correct answer)
Roentgen (R)
Sievert (Sv)
Becquerel (Bq)

Correct answer: Gray (Gy)

The Gray (Gy) is the SI unit of absorbed dose, equal to 1 joule of energy deposited per kilogram of tissue.

Question 156: During a PM on a defibrillator, the BMET checks delivered energy. What instrument is used to measure this?

ECG simulator
Oscilloscope only
Defibrillator analyzer (Correct answer)
Multimeter

Correct answer: Defibrillator analyzer

A defibrillator analyzer measures delivered energy in joules, charge time, and waveform characteristics during PM testing.

Question 157: Why is static IP addressing often preferred over DHCP for critical medical devices on a hospital network?

Static IPs ensure the device always has the same address, preventing communication failures if DHCP is unavailable (Correct answer)
Static IPs automatically encrypt device traffic
Static IPs use less network bandwidth
Static IPs provide faster network speeds

Correct answer: Static IPs ensure the device always has the same address, preventing communication failures if DHCP is unavailable

Static IP addresses ensure critical medical devices always have a predictable, consistent network address.

Question 158: During annual PM on a mechanical ventilator, which test is MOST critical for patient safety regarding oxygen delivery?

Calibration and accuracy check of the oxygen sensor/analyzer (Correct answer)
Verification of the humidifier thermostat accuracy
Testing the exhalation valve seal
Measuring peak inspiratory flow rate

Correct answer: Calibration and accuracy check of the oxygen sensor/analyzer

The oxygen sensor (typically a galvanic fuel cell) degrades over time and can drift, causing the ventilator to deliver incorrect FiO₂. Delivering too little O₂ causes hypoxia; too much causes oxygen toxicity. Calibrating and verifying oxygen sensor accuracy is a mandatory safety check. While exhalation valve and humidifier checks are important, an FiO₂ error can be immediately life-threatening.

Question 159: In a full-wave bridge rectifier with four diodes, the output ripple frequency relative to the AC input frequency is:

Equal (1×)
Four times (4×)
Double (2×) (Correct answer)
Half (0.5×)

Correct answer: Double (2×)

A full-wave bridge rectifier conducts on both half-cycles, producing two output pulses per input cycle, doubling the ripple frequency.

Question 160: Which ANSI/AAMI standard governs the comprehensive reprocessing of reusable medical devices?

ANSI/AAMI ST41
ANSI/AAMI ST58
ANSI/AAMI ST79 (Correct answer)
ANSI/AAMI ST67

Correct answer: ANSI/AAMI ST79

ANSI/AAMI ST79 is the comprehensive guide to steam sterilization and sterility assurance in healthcare facilities and covers all aspects of device reprocessing.

Question 161: A BIOMED technician notices that medical device telemetry data is dropping packets on the hospital Wi-Fi. Which QoS mechanism should be prioritized to ensure reliable transmission?

Spanning Tree Protocol
MAC address filtering
Best-effort delivery
Weighted Fair Queuing (WFQ) with medical traffic class (Correct answer)

Correct answer: Weighted Fair Queuing (WFQ) with medical traffic class

Weighted Fair Queuing assigns higher priority to critical medical traffic classes, reducing dropped packets for telemetry.

Question 162: Which document should a BMET consult first to determine PM intervals for a newly acquired ventilator?

OSHA 29 CFR 1910 general industry standards
The manufacturer's service manual and recommended maintenance schedule (Correct answer)
The hospital's infection control policy
The previous facility's PM records

Correct answer: The manufacturer's service manual and recommended maintenance schedule

Manufacturer service manuals contain device-specific PM intervals based on engineering design life and regulatory submissions, making them the primary reference.

Question 163: During PM on an electrocoagulation unit, the output power is measured 15% below the displayed setting. Which step should the technician perform next?

Increase the generator voltage supply rail
Tag the device out of service immediately
Replace the RF output transformer
Adjust the internal power calibration potentiometer per service manual (Correct answer)

Correct answer: Adjust the internal power calibration potentiometer per service manual

A 15% power output deviation is within the range correctable by internal calibration adjustment before component replacement is warranted.

Question 164: A pneumatic tourniquet used in orthopedic surgery is displaying pressure that fluctuates ±30 mmHg during inflation. The MOST likely cause is:

Low wall gas supply pressure
Incorrect limb occlusion pressure setting
Leak in the cuff bladder or connecting tubing (Correct answer)
Cuff applied over excessive padding

Correct answer: Leak in the cuff bladder or connecting tubing

Pressure fluctuations in a pneumatic tourniquet are most commonly caused by air leaks in the cuff bladder or tubing connections.

Question 165: In the context of EEG monitoring, which brain wave frequency is associated with deep, dreamless sleep?

Delta waves (0.5–4 Hz) (Correct answer)
Alpha waves (8–13 Hz)
Beta waves (13–30 Hz)
Theta waves (4–8 Hz)

Correct answer: Delta waves (0.5–4 Hz)

Delta waves have the lowest frequency and highest amplitude and predominate during deep (stage 3–4) non-REM sleep.

Question 166: A sphygmomanometer with the warning that the pressure reading is usually excessive is brought in for duty. What is the MOST suitable procedure to inspect the device?

Request a test of the device on another patient to examine it in use
Recalibrate the device's manometer and return to service
Visually inspect the sphygmomanometer's inflatable cuff and patch it
Perform a test run on the device on a noninvasive blood pressure simulator (Correct answer)

Correct answer: Perform a test run on the device on a noninvasive blood pressure simulator

When a sphygmomanometer is reported to give excessive pressure readings, the most accurate inspection procedure is to use a noninvasive blood pressure (NIBP) simulator. This specialized device can generate precise, known blood pressure values, allowing the technician to objectively verify the accuracy of the sphygmomanometer's measurements against these controlled standards. This method ensures a reliable assessment of the device's calibration and function.

CBET (Certified Biomedical Equipment Technician) Exam

The CBET (Certified Biomedical Equipment Technician) Exam exam validates essential knowledge and skills required for certification or licensure in this field.

165

Questions

210 min

Time Limit

68%

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