Q.1 What is the primary purpose of calibrating a biomedical instrument?
To improve its aesthetic appearance
To ensure measurement accuracy against known standards
To increase its power consumption
To extend its warranty period
Explanation - Calibration aligns the instrument’s output with reference standards, guaranteeing that its measurements are accurate and reliable.
Correct answer is: To ensure measurement accuracy against known standards
Q.2 Which international standard defines safety requirements for medical electrical equipment?
ISO 9001
IEC 60601
IEEE 802.11
ISO 14001
Explanation - IEC 60601 is the globally recognized series of standards that addresses safety and essential performance of medical electrical devices.
Correct answer is: IEC 60601
Q.3 In the context of calibration, what does the term “span” refer to?
The time taken to perform calibration
The difference between the maximum and minimum calibrated values
The number of calibration points used
The physical size of the instrument
Explanation - Span is the calibrated range of the instrument, defined as the difference between its upper and lower limits.
Correct answer is: The difference between the maximum and minimum calibrated values
Q.4 Which of the following is a common method for checking the isolation resistance of a medical device?
Using a multimeter in continuity mode
Applying a high‑voltage megohmmeter (Hipot) test
Measuring the device’s temperature
Observing the LED indicators
Explanation - A Hipot test applies a high voltage to verify that there is sufficient insulation resistance between patient‑connected parts and the device chassis.
Correct answer is: Applying a high‑voltage megohmmeter (Hipot) test
Q.5 What does the abbreviation ‘LE’ stand for in IEC 60601‑1 safety terminology?
Limited Exposure
Leakage Current, Earth‑grounded
Maximum Allowable Leakage Current
Low Energy
Explanation - LE denotes the maximum permissible leakage current that can flow from the device to the patient under normal conditions.
Correct answer is: Maximum Allowable Leakage Current
Q.6 Which calibration artifact is commonly used to verify the accuracy of an ECG machine?
A pressure cuff phantom
A sinusoidal signal generator with known amplitude and frequency
A glucose solution
A temperature probe
Explanation - ECG calibrators provide standard waveforms (e.g., sine waves) with known amplitude and frequency to check the ECG’s gain and frequency response.
Correct answer is: A sinusoidal signal generator with known amplitude and frequency
Q.7 Which regulatory body is primarily responsible for ensuring the safety of medical devices in the United States?
European Medicines Agency (EMA)
Food and Drug Administration (FDA)
Health Canada
World Health Organization (WHO)
Explanation - The FDA’s Center for Devices and Radiological Health (CDRH) oversees the safety and effectiveness of medical devices in the U.S.
Correct answer is: Food and Drug Administration (FDA)
Q.8 What is the typical maximum allowable patient leakage current for a Class I medical device according to IEC 60601‑1?
10 mA
100 µA
1 mA
5 mA
Explanation - IEC 60601‑1 limits patient leakage current for Class I devices to 10 mA under normal conditions to prevent harmful shocks.
Correct answer is: 10 mA
Q.9 Which standard specifies requirements for the electromagnetic compatibility (EMC) of medical electrical equipment?
IEC 60601‑1‑2
ISO 9001
IEEE 802.3
ISO 13485
Explanation - IEC 60601‑1‑2 addresses EMC, ensuring that devices neither emit nor are susceptible to electromagnetic disturbances beyond acceptable limits.
Correct answer is: IEC 60601‑1‑2
Q.10 During a calibration check, a pulse oximeter consistently reads 2 % higher than the reference value. Which type of error is this?
Random error
Systematic error
Zero‑shift error
Noise error
Explanation - A consistent offset (2 % higher) indicates a systematic error, often caused by calibration drift or bias.
Correct answer is: Systematic error
Q.11 What does ISO 13485 specifically address?
Environmental management systems
Quality management systems for medical devices
Occupational health and safety
Information security
Explanation - ISO 13485 defines requirements for a quality management system where an organization needs to demonstrate its ability to provide medical devices that meet customer and regulatory requirements.
Correct answer is: Quality management systems for medical devices
Q.12 Which of the following is NOT a typical step in the calibration of a sphygmomanometer (blood pressure monitor)?
Connecting the device to a calibrated pressure source
Adjusting the cuff size to fit the patient’s arm
Comparing displayed pressure with the reference pressure
Recording the deviation and applying correction factors
Explanation - Cuff sizing is a clinical usage consideration, not a calibration step. Calibration involves comparing readings against a known pressure source.
Correct answer is: Adjusting the cuff size to fit the patient’s arm
Q.13 In risk management for biomedical devices, what does the term ‘hazard’ refer to?
A device’s cost overruns
Potential source of harm
A marketing strategy
The device’s warranty period
Explanation - A hazard is any potential source of harm, such as electrical shock, infection, or radiation, that can affect patients, users, or the environment.
Correct answer is: Potential source of harm
Q.14 Which calibration interval is most appropriate for a bedside patient monitor that is used daily in a busy ICU?
Every 5 years
Every 2 years
Every 6 months
Every 10 years
Explanation - High‑usage critical devices typically require more frequent calibration, often semi‑annually, to maintain accuracy and safety.
Correct answer is: Every 6 months
Q.15 What is the purpose of a ‘phantom’ in the calibration of imaging equipment such as ultrasound or MRI?
To simulate patient anatomy for testing performance
To store patient data securely
To increase the device’s power output
To act as a battery backup
Explanation - Phantoms are specially designed objects that mimic the acoustic or magnetic properties of tissue, allowing verification of image quality and accuracy.
Correct answer is: To simulate patient anatomy for testing performance
Q.16 Which of the following best describes ‘repeatability’ in the context of instrument performance?
The ability to produce the same result under unchanged conditions over multiple trials
The speed at which measurements can be taken
The range of temperatures over which the device operates
The device’s resistance to physical shock
Explanation - Repeatability refers to the consistency of measurements when the same operator uses the same device under identical conditions.
Correct answer is: The ability to produce the same result under unchanged conditions over multiple trials
Q.17 Which document outlines the essential performance requirements for a new medical device in the European Union?
CE Marking Technical File
FDA 510(k) submission
ISO 14971 Risk Management Report
IEC 62304 Software Lifecycle
Explanation - The Technical File (or Design Dossier) contains evidence that a device meets the EU’s Essential Requirements, enabling CE marking.
Correct answer is: CE Marking Technical File
Q.18 When calibrating a thermistor‑based temperature sensor, which reference device is most appropriate?
A calibrated mercury-in-glass thermometer
A digital multimeter set to voltage mode
An oscilloscope
A pressure transducer
Explanation - A traceable, high‑accuracy thermometer provides a reliable temperature reference for calibrating thermistor sensors.
Correct answer is: A calibrated mercury-in-glass thermometer
Q.19 Which of the following is a key requirement of IEC 60601‑1 regarding device grounding?
All devices must be battery powered
The device chassis must be isolated from patient‑connected parts
Devices should never use earth ground
Grounding is optional for Class III devices
Explanation - IEC 60601‑1 mandates protective earth (PE) grounding or equivalent isolation to prevent hazardous currents from reaching the patient.
Correct answer is: The device chassis must be isolated from patient‑connected parts
Q.20 What does the term ‘linearity’ refer to in a calibrated sensor’s performance?
The sensor’s ability to operate without power
The proportional relationship between input and output across the measurement range
The speed at which the sensor responds to changes
The sensor’s resistance to corrosion
Explanation - Linearity indicates how closely the sensor’s output follows a straight line when plotted against the true input value.
Correct answer is: The proportional relationship between input and output across the measurement range
Q.21 Which standard is specifically concerned with the safety of medical electrical equipment used in home healthcare environments?
IEC 60601‑1‑11
ISO 9001
IEEE 11073
ISO 13485
Explanation - IEC 60601‑1‑11 provides additional safety and performance requirements for medical devices used in the home.
Correct answer is: IEC 60601‑1‑11
Q.22 During a safety inspection, a medical device shows a patient leakage current of 12 mA. According to IEC 60601‑1, what action should be taken?
No action needed; it is within limits
Device must be taken out of service until repaired
Increase the device’s power supply voltage
Replace the device’s battery only
Explanation - The maximum allowed patient leakage current for most Class I devices is 10 mA; exceeding this requires the device to be withdrawn from use until corrected.
Correct answer is: Device must be taken out of service until repaired
Q.23 Which of the following best describes a ‘traceability chain’ in calibration?
A sequence of measurements that links a device to national standards
A method for tracking device location in a hospital
A software algorithm for data encryption
A list of device users
Explanation - Traceability ensures that calibration results can be related to an unbroken chain of comparisons to national or international standards.
Correct answer is: A sequence of measurements that links a device to national standards
Q.24 In the context of biomedical device standards, what does the abbreviation ‘MDR’ stand for?
Medical Device Regulation
Maximum Device Resistance
Medical Data Repository
Manufacturing Design Review
Explanation - MDR refers to the European Union’s Medical Device Regulation (EU) 2017/745, which governs the safety and performance of medical devices.
Correct answer is: Medical Device Regulation
Q.25 Which parameter is most critical when calibrating a pulse oximeter’s accuracy?
Ambient temperature
Wavelength of emitted light
Battery voltage
Physical size of the probe
Explanation - Pulse oximeters rely on specific red and infrared wavelengths; calibration must verify that the device correctly interprets absorption at these wavelengths.
Correct answer is: Wavelength of emitted light
Q.26 What is the main benefit of implementing ISO 14971 in the development of a medical device?
Improved marketing strategy
Systematic risk management throughout the product lifecycle
Reduced power consumption
Enhanced aesthetic design
Explanation - ISO 14971 provides a framework for identifying, evaluating, and controlling risks associated with medical devices.
Correct answer is: Systematic risk management throughout the product lifecycle
Q.27 Which calibration technique is best suited for verifying the frequency response of an EEG amplifier?
Applying a series of sine wave inputs at different frequencies
Measuring DC voltage offset
Testing with a static pressure source
Using a temperature bath
Explanation - Frequency response is assessed by injecting sine waves across the relevant bandwidth and observing gain and phase characteristics.
Correct answer is: Applying a series of sine wave inputs at different frequencies
Q.28 Which of the following is NOT a typical requirement of IEC 60601‑1 for medical electrical equipment?
Electrical safety
Software licensing fees
Electromagnetic compatibility
Performance testing
Explanation - IEC 60601‑1 focuses on safety, EMC, and performance, not on commercial aspects such as licensing fees.
Correct answer is: Software licensing fees
Q.29 A defibrillator is classified under which IEC 60601 device class?
Class I
Class II
Class III
Class IV
Explanation - Class III devices are high‑risk devices that are directly connected to the heart or central nervous system and require the most stringent controls.
Correct answer is: Class III
Q.30 Which of the following best describes ‘accuracy’ of a calibrated instrument?
The closeness of repeated measurements to each other
The difference between the measured value and the true value
The speed at which measurements are taken
The range of temperatures the instrument can measure
Explanation - Accuracy quantifies how close a measurement is to the actual or reference value.
Correct answer is: The difference between the measured value and the true value
Q.31 When performing a calibration check, you notice a drift of 0.5 °C in a temperature sensor over a 24‑hour period. This drift is an example of:
Random error
Systematic error
Calibration offset
Stability issue
Explanation - Drift over time reflects the sensor’s stability; it indicates that the device’s output changes even when the input remains constant.
Correct answer is: Stability issue
Q.32 Which of the following is a key consideration when selecting a reference standard for calibrating a blood glucose meter?
The reference solution must be traceable to a national standard
The reference solution should be bright colored
The reference solution must be refrigerated at all times
The reference solution should be disposable
Explanation - Traceability ensures that the reference material’s concentration is known accurately, providing a reliable basis for calibration.
Correct answer is: The reference solution must be traceable to a national standard
Q.33 Which safety feature helps protect patients from excessive voltage in a medical device?
Overcurrent protection fuse
Colorful casing
Bluetooth connectivity
LCD display
Explanation - An overcurrent fuse interrupts the circuit when current exceeds safe limits, preventing hazardous voltages from reaching the patient.
Correct answer is: Overcurrent protection fuse
Q.34 Which of the following best defines ‘precision’ in the context of biomedical instrumentation?
How close a measurement is to the true value
The repeatability of measurements under unchanged conditions
The speed at which a measurement is taken
The device’s power consumption
Explanation - Precision reflects the consistency of repeated measurements, regardless of their closeness to the true value.
Correct answer is: The repeatability of measurements under unchanged conditions
Q.35 Which of the following documents is required for a CE‑marked medical device before it can be placed on the EU market?
Declaration of Conformity (DoC)
User manual in PDF format
Marketing brochure
Patent certificate
Explanation - The DoC declares that the device meets all applicable EU directives and standards, enabling CE marking.
Correct answer is: Declaration of Conformity (DoC)
Q.36 In a calibration laboratory, which environmental condition is most critical to control for accurate electrical measurements?
Ambient humidity
Room temperature
Noise level
Lighting intensity
Explanation - Temperature variations can affect resistance, voltage references, and other electrical parameters, influencing measurement accuracy.
Correct answer is: Room temperature
Q.37 Which term describes the maximum permissible exposure to electromagnetic fields for patients and staff near a medical device?
Specific Absorption Rate (SAR)
Signal‑to‑Noise Ratio (SNR)
Maximum Allowable Leakage Current (MALC)
Peak Power Rating (PPR)
Explanation - SAR quantifies the rate at which energy is absorbed by human tissue when exposed to an electromagnetic field.
Correct answer is: Specific Absorption Rate (SAR)
Q.38 Which of the following is a primary goal of the ISO 14971 risk management process?
Minimize production cost
Eliminate all possible risks
Identify, evaluate, and control hazards
Increase market share
Explanation - ISO 14971 provides a systematic approach to manage risks throughout the device lifecycle, not to eliminate all risk or focus on cost.
Correct answer is: Identify, evaluate, and control hazards
Q.39 When calibrating a flow sensor used in respiratory monitoring, which reference instrument is most appropriate?
A calibrated gas syringe delivering known volumes
A thermocouple
A pressure transducer
A digital camera
Explanation - A gas syringe can provide accurate, known volumes of gas to verify the flow sensor’s output.
Correct answer is: A calibrated gas syringe delivering known volumes
Q.40 What does the term ‘dead‑time’ refer to in the context of a pulse oximeter’s measurement cycle?
The time required to power on the device
The interval between successive light emission cycles
The time taken to replace the sensor probe
The time needed for data storage
Explanation - Dead‑time is the brief pause between the emission of red and infrared light, crucial for accurate SpO₂ calculations.
Correct answer is: The interval between successive light emission cycles
Q.41 Which standard outlines the requirements for software in medical devices?
IEC 62304
ISO 9001
IEEE 802.11
ISO 13485
Explanation - IEC 62304 provides a lifecycle process for medical device software development and maintenance.
Correct answer is: IEC 62304
Q.42 During a safety test, a device’s earth leakage current is measured at 0.3 mA. According to IEC 60601‑1, this value is:
Above the acceptable limit
Within acceptable limits for Class I equipment
Too low to be measured accurately
Irrelevant for safety assessment
Explanation - IEC 60601‑1 typically permits earth leakage currents up to 0.5 mA for Class I devices, so 0.3 mA is acceptable.
Correct answer is: Within acceptable limits for Class I equipment
Q.43 Which of the following best describes a ‘bias error’ in a calibrated sensor?
A random fluctuation around the true value
A consistent offset from the true value
An error caused by temperature changes
A delay in sensor response
Explanation - Bias error is a systematic deviation that shifts all measurements by the same amount.
Correct answer is: A consistent offset from the true value
Q.44 Which of the following is a requirement for a medical device to obtain FDA 510(k) clearance?
Proof of clinical superiority over all existing devices
Demonstration of substantial equivalence to a legally marketed predicate device
Aesthetic design approval
Manufacturing in a foreign country
Explanation - The 510(k) pathway requires showing that the new device is as safe and effective as a previously cleared device.
Correct answer is: Demonstration of substantial equivalence to a legally marketed predicate device
Q.45 A biomedical instrument exhibits a non‑linear response at high input levels. Which calibration approach can best correct this behavior?
Single‑point zero adjustment
Multi‑point calibration curve fitting
Replacing the power supply
Increasing the sampling rate
Explanation - Using several calibration points across the range allows creation of a correction curve that accounts for non‑linearity.
Correct answer is: Multi‑point calibration curve fitting
Q.46 Which of the following is NOT a typical component of a calibration report?
Instrument serial number
Reference standards used and their traceability
The technician’s favorite color
Measured values and comparison to reference
Explanation - A calibration report includes identification, reference standards, measurement data, and conclusions, but not personal preferences.
Correct answer is: The technician’s favorite color
Q.47 What is the primary purpose of a ‘protective earth (PE) conductor’ in medical equipment wiring?
To provide a backup power source
To ensure a low‑impedance path for fault currents
To transmit data signals
To reduce device weight
Explanation - PE conductors safely conduct fault currents to earth, reducing the risk of electric shock.
Correct answer is: To ensure a low‑impedance path for fault currents
Q.48 Which standard specifically addresses the safety of medical electrical equipment used in the home environment?
IEC 60601‑1‑11
ISO 9001
IEEE 802.3
ISO 27001
Explanation - IEC 60601‑1‑11 extends the basic safety requirements to include considerations for home use.
Correct answer is: IEC 60601‑1‑11
Q.49 A temperature sensor is calibrated at 0 °C, 25 °C, and 100 °C. The sensor’s output at 25 °C deviates by +0.2 °C. This deviation is an example of:
Zero‑shift error
Span error
Mid‑scale non‑linearity
Random noise
Explanation - A deviation at the middle of the range indicates a non‑linearity error rather than a pure offset (zero‑shift) or span error.
Correct answer is: Mid‑scale non‑linearity
Q.50 Which of the following actions is recommended when a calibrated device shows a drift beyond its allowable tolerance?
Ignore the drift if the device still works
Schedule a re‑calibration and investigate the cause
Increase the device’s power supply voltage
Replace the device’s user manual
Explanation - Drift indicates loss of accuracy; the device should be recalibrated and the underlying cause identified.
Correct answer is: Schedule a re‑calibration and investigate the cause
Q.51 Which of the following is a typical performance parameter assessed during the validation of a new ECG monitor?
Battery life under continuous operation
Signal‑to‑Noise Ratio (SNR)
Device weight
Color of the display
Explanation - SNR quantifies the clarity of the ECG signal relative to background noise, a critical performance metric.
Correct answer is: Signal‑to‑Noise Ratio (SNR)
Q.52 In IEC 60601‑1, what does the term ‘protective earth’ (PE) refer to?
A separate power supply for the device
A grounding conductor that provides a path for fault currents
The device’s internal battery
A wireless communication protocol
Explanation - PE is a safety ground that helps limit voltage on exposed conductive parts during fault conditions.
Correct answer is: A grounding conductor that provides a path for fault currents
Q.53 Which of the following is a primary advantage of using a digital multimeter (DMM) for verifying voltage outputs during calibration?
It can measure voltage without any external power source
It provides high accuracy and resolution
It automatically corrects any errors
It is waterproof
Explanation - DMMs are designed for precise voltage measurement, making them ideal for calibration verification.
Correct answer is: It provides high accuracy and resolution
Q.54 Which of the following is a key reason for performing a ‘post‑calibration verification’ after a device has been calibrated?
To ensure the calibration actually improved accuracy
To update the device’s software license
To change the device’s color scheme
To increase the device’s weight
Explanation - Verification confirms that the calibration adjustments have brought the instrument within its specified performance limits.
Correct answer is: To ensure the calibration actually improved accuracy
Q.55 Which of the following best describes a ‘Class I’ medical device under IEC 60601‑1?
A device with no patient contact
A device with low risk that requires only basic safety requirements
A device that must be implanted permanently
A device that is only used for research
Explanation - Class I devices are considered low‑risk and need to meet the essential safety requirements without extensive additional controls.
Correct answer is: A device with low risk that requires only basic safety requirements
Q.56 When calibrating a pressure transducer used in invasive blood pressure monitoring, which reference standard is most suitable?
A calibrated mercury manometer
A digital thermometer
A light sensor
A voltage reference source
Explanation - Mercury manometers provide highly accurate pressure references, ideal for calibrating pressure transducers.
Correct answer is: A calibrated mercury manometer
Q.57 What is the primary purpose of performing an ‘electromagnetic compatibility (EMC)’ test on a biomedical device?
To verify the device’s resistance to physical impact
To ensure the device does not emit or suffer from unacceptable electromagnetic interference
To assess the device’s battery life
To test the device’s waterproofing
Explanation - EMC testing confirms that a device can operate safely alongside other equipment without causing or receiving harmful interference.
Correct answer is: To ensure the device does not emit or suffer from unacceptable electromagnetic interference
Q.58 A calibrated syringe pump delivers 10 mL/min but the actual flow measured is 9.5 mL/min. The error is primarily due to:
Random noise
Systematic bias
Temperature fluctuations
Battery depletion
Explanation - The consistent 5 % shortfall indicates a systematic bias in the pump’s calibration.
Correct answer is: Systematic bias
Q.59 Which of the following statements about ISO 9001 is true in the context of biomedical instrumentation?
It is a standard specifically for medical device safety
It focuses on quality management systems applicable to any organization
It prescribes detailed calibration procedures for all devices
It is a legal requirement for all medical devices
Explanation - ISO 9001 provides a generic framework for quality management, not specific safety or calibration rules.
Correct answer is: It focuses on quality management systems applicable to any organization
Q.60 In the context of calibration, what does the term ‘uncertainty budget’ refer to?
The financial cost of the calibration process
A compilation of all individual sources of measurement uncertainty
The time required to complete the calibration
The number of devices calibrated per day
Explanation - An uncertainty budget aggregates contributions from all error sources to estimate the overall measurement uncertainty.
Correct answer is: A compilation of all individual sources of measurement uncertainty
Q.61 Which of the following is a requirement for a medical device to be classified as ‘CE marked’ under the EU MDR?
The device must be manufactured in the United States
The device must meet the essential requirements and have a valid Declaration of Conformity
The device must be free of all risks
The device must be priced below a specific threshold
Explanation - CE marking indicates conformity with EU legislation, demonstrated through a DoC and meeting essential requirements.
Correct answer is: The device must meet the essential requirements and have a valid Declaration of Conformity
Q.62 During a safety check, a medical device’s isolation resistance is measured at 5 MΩ. According to IEC 60601‑1, this value is:
Acceptable for most Class I devices
Too low and indicates a safety hazard
Irrelevant for safety assessment
Only relevant for Class III devices
Explanation - IEC 60601‑1 typically requires isolation resistance of at least 1 MΩ for Class I devices, but higher values (≥10 MΩ) are preferred; 5 MΩ may be marginal and warrants investigation.
Correct answer is: Too low and indicates a safety hazard
Q.63 Which of the following is a characteristic of a ‘digital calibration’ method?
It uses physical adjustment screws
It applies software corrections to the instrument’s output
It requires a mechanical ruler
It changes the device’s hardware components
Explanation - Digital calibration often involves adjusting parameters in firmware or software to align output with reference values.
Correct answer is: It applies software corrections to the instrument’s output
Q.64 Which organization publishes the IEC 60601 series of standards?
International Electrotechnical Commission
Institute of Electrical and Electronics Engineers
World Health Organization
American National Standards Institute
Explanation - The IEC develops and publishes international standards for electrical, electronic, and related technologies, including IEC 60601.
Correct answer is: International Electrotechnical Commission
Q.65 A device’s calibration certificate lists a ‘combined standard uncertainty’ of 0.2 °C. What does this value represent?
The exact error in each measurement
The estimated range within which the true value lies with a certain confidence level
The maximum temperature the device can measure
The device’s operating temperature
Explanation - Combined standard uncertainty quantifies the overall measurement uncertainty, indicating the confidence interval for the true value.
Correct answer is: The estimated range within which the true value lies with a certain confidence level
Q.66 Which of the following best describes a ‘protective earth (PE) fault’ in a medical device?
A fault that disconnects the device from the power source
A condition where the protective earth conductor is missing or broken
A software error in the device’s user interface
A temperature sensor malfunction
Explanation - A PE fault means the safety grounding path is compromised, increasing shock risk.
Correct answer is: A condition where the protective earth conductor is missing or broken
Q.67 What is the primary purpose of performing a ‘functional safety analysis’ on a biomedical instrument?
To evaluate the device’s color scheme
To assess how failures could affect patient safety
To calculate the device’s power consumption
To design the device’s packaging
Explanation - Functional safety analysis identifies potential failure modes and their impact on safety, guiding risk mitigation.
Correct answer is: To assess how failures could affect patient safety
Q.68 In a calibration setup, why is it important to allow the instrument to warm up before taking measurements?
To ensure the device reaches thermal equilibrium, minimizing drift
To increase the device’s battery life
To make the device more comfortable for the user
To reduce the device’s weight
Explanation - Warm‑up stabilizes internal components, reducing temperature‑related measurement drift.
Correct answer is: To ensure the device reaches thermal equilibrium, minimizing drift
Q.69 Which of the following is a typical tolerance for the accuracy of a clinical-grade pulse oximeter?
±10 % SpO₂
±0.1 % SpO₂
±2 % SpO₂
±20 % SpO₂
Explanation - Clinical pulse oximeters are generally required to have an accuracy within ±2 % over the normal SpO₂ range.
Correct answer is: ±2 % SpO₂
Q.70 Which standard specifies the requirements for the labeling of medical devices in the European Union?
IEC 60601‑1‑2
ISO 13485
MDR Annex I
ISO 9001
Explanation - MDR Annex I outlines essential requirements, including labeling, for medical devices marketed in the EU.
Correct answer is: MDR Annex I
Q.71 A biomedical device is to be used in an operating room with high electromagnetic noise. Which design feature helps ensure reliable operation?
Use of shielded cables and proper grounding
Bright colored housing
Large LCD display
Wireless connectivity
Explanation - Shielded cables and proper grounding mitigate EMI, preserving signal integrity in noisy environments.
Correct answer is: Use of shielded cables and proper grounding
Q.72 Which of the following best describes the term ‘calibration interval’?
The time taken to perform a single calibration step
The period between successive calibrations of a device
The distance between the device and the reference standard
The number of users that can operate the device
Explanation - Calibration interval defines how often a device must be recalibrated to maintain accuracy.
Correct answer is: The period between successive calibrations of a device
Q.73 Which of the following is a primary benefit of using ISO 13485 certification for a biomedical device manufacturer?
Guarantee of zero product defects
Demonstration of a quality management system specific to medical devices
Automatic approval in all global markets
Reduced need for technical staff
Explanation - ISO 13485 certifies that a manufacturer follows a QMS tailored to the medical device industry, facilitating regulatory compliance.
Correct answer is: Demonstration of a quality management system specific to medical devices
Q.74 When a device’s calibration curve shows a non‑linear region at low inputs, which calibration technique can improve accuracy there?
Increase the device’s power supply voltage
Add more calibration points in the low‑input region
Reduce the sampling rate
Replace the device’s casing
Explanation - Increasing data points where non‑linearity occurs allows a better fit and correction of the calibration curve.
Correct answer is: Add more calibration points in the low‑input region
Q.75 Which of the following best defines ‘electrical safety’ for a medical device?
The device’s ability to operate without any power source
Protection against electric shock, burns, and other hazards to patients and users
The device’s resistance to water damage
The device’s battery life
Explanation - Electrical safety ensures that devices do not expose patients or operators to hazardous electrical conditions.
Correct answer is: Protection against electric shock, burns, and other hazards to patients and users
Q.76 Which of the following is an example of a ‘primary standard’ used for calibration traceability?
A calibrated digital multimeter
A national reference kilogram weight
A user manual
A device’s LCD screen
Explanation - Primary standards are the highest‑level references (e.g., national standards) from which all other measurements are derived.
Correct answer is: A national reference kilogram weight
Q.77 During a safety test, a medical device’s ‘leakage current’ is measured to be 150 µA. According to IEC 60601‑1, this value is:
Above the limit for Class I devices
Within the acceptable limit for Class I devices
Too low to be measured accurately
Irrelevant for safety assessment
Explanation - IEC 60601‑1 typically allows leakage currents up to 500 µA for Class I devices under normal conditions.
Correct answer is: Within the acceptable limit for Class I devices
Q.78 Which of the following is a required element of a device’s ‘risk management file’ per ISO 14971?
A list of all suppliers
A hazard analysis with associated risk control measures
The device’s marketing plan
Employee salary records
Explanation - ISO 14971 mandates a documented risk management file that includes hazard identification, risk analysis, evaluation, and control measures.
Correct answer is: A hazard analysis with associated risk control measures
Q.79 What is the primary advantage of using a ‘reference grade’ instrument in calibration?
It is cheaper than other instruments
It provides higher accuracy and traceability
It has a longer battery life
It can be used without any training
Explanation - Reference grade instruments are calibrated against primary standards, ensuring superior accuracy for calibrations.
Correct answer is: It provides higher accuracy and traceability
Q.80 Which of the following is a typical calibration method for a digital thermometer used in clinical settings?
Comparison with a calibrated ice‑water bath (0 °C) and boiling water (100 °C)
Measuring voltage output with a multimeter
Testing with a pressure gauge
Using a light intensity sensor
Explanation - Ice‑water and boiling water provide fixed temperature references for verifying thermometer accuracy.
Correct answer is: Comparison with a calibrated ice‑water bath (0 °C) and boiling water (100 °C)
Q.81 Which of the following best describes a ‘Class II’ medical device under IEC 60601‑1?
A device with no electrical components
A device requiring additional protection measures beyond basic safety
A disposable single‑use device
A device only used for research
Explanation - Class II devices have higher risk than Class I and need extra safety controls, such as additional protective measures.
Correct answer is: A device requiring additional protection measures beyond basic safety
Q.82 During calibration of a biomedical amplifier, a technician observes a gain error of 3 % at the high‑frequency end. Which performance parameter is most affected?
Linearity
Frequency response
Zero offset
Battery life
Explanation - A gain error that varies with frequency indicates an issue with the amplifier’s frequency response.
Correct answer is: Frequency response
Q.83 Which of the following is a key feature of IEC 60601‑1‑8?
Guidelines for medical device software lifecycle
Requirements for usability engineering of medical devices
Standards for wireless communication
Procedures for device decommissioning
Explanation - IEC 60601‑1‑8 addresses the usability aspects to ensure safe and effective use of medical devices.
Correct answer is: Requirements for usability engineering of medical devices
Q.84 When a device’s calibration certificate states a ‘coverage factor’ of k=2, what does this imply about the reported uncertainty?
The uncertainty is doubled for safety reasons
The true value is expected to lie within ±2 times the standard uncertainty with approximately 95 % confidence
The device was calibrated twice
The device can operate at twice its normal voltage
Explanation - A coverage factor of k=2 expands the standard uncertainty to a confidence interval of about 95 %.
Correct answer is: The true value is expected to lie within ±2 times the standard uncertainty with approximately 95 % confidence
Q.85 Which of the following is the most appropriate action if a calibrated ECG device fails a repeatability test?
Ignore the result if the device powers on
Re‑calibrate the device and investigate mechanical or electrical causes of variability
Replace the device’s battery only
Increase the device’s volume
Explanation - Failure in repeatability suggests instability; the device should be recalibrated and the root cause examined.
Correct answer is: Re‑calibrate the device and investigate mechanical or electrical causes of variability
Q.86 Which of the following best defines the term ‘safety margin’ in biomedical instrumentation?
The difference between the device’s price and its market value
The extra capacity built into the design to tolerate unexpected conditions
The number of users allowed to operate the device simultaneously
The distance between the device and the patient
Explanation - Safety margin provides a buffer to ensure safe operation even when conditions deviate from the nominal design.
Correct answer is: The extra capacity built into the design to tolerate unexpected conditions
Q.87 In calibration, what is meant by ‘zero adjustment’?
Changing the device’s color to zero
Setting the output to zero when the input is zero to eliminate offset error
Increasing the device’s maximum range
Reducing the device’s power consumption to zero
Explanation - Zero adjustment removes any constant offset that appears when the input signal is zero.
Correct answer is: Setting the output to zero when the input is zero to eliminate offset error
Q.88 Which of the following is a primary goal of the FDA’s Quality System Regulation (QSR) for medical devices?
To control the pricing of medical devices
To ensure devices are designed and produced consistently to meet safety and effectiveness requirements
To limit the number of devices that can be sold internationally
To regulate the color schemes of device displays
Explanation - The QSR (21 CFR 820) mandates a quality management system that assures consistent device safety and performance.
Correct answer is: To ensure devices are designed and produced consistently to meet safety and effectiveness requirements
Q.89 A biomedical instrument is required to operate in a magnetic resonance imaging (MRI) suite. Which standard primarily governs its safety?
IEC 60601‑1‑2
IEC 60601‑1‑8
IEC 60601‑2‑33
ISO 13485
Explanation - IEC 60601‑2‑33 addresses the safety and essential performance of MRI equipment and related devices.
Correct answer is: IEC 60601‑2‑33
Q.90 Which of the following best describes the concept of ‘traceability’ in calibration?
The ability to locate the device in a hospital
Linking measurement results to national or international standards through an unbroken chain of comparisons
The speed at which a device can be calibrated
The number of users who can operate the device
Explanation - Traceability ensures that measurement results are credible and comparable worldwide.
Correct answer is: Linking measurement results to national or international standards through an unbroken chain of comparisons
Q.91 During calibration of a pulse oximeter, a technician uses a reference oxygen saturation simulator set to 97 % SpO₂. The device reads 94 %. This discrepancy is most likely due to:
Random noise
Systematic bias in the sensor’s calibration
Battery depletion
Ambient temperature
Explanation - A consistent offset indicates a systematic calibration error rather than random variation.
Correct answer is: Systematic bias in the sensor’s calibration
Q.92 Which of the following is a typical requirement for a medical device to achieve CE marking under the EU MDR?
Demonstration of conformity with the relevant EU harmonized standards
Manufacturing in a European Union country only
Zero cost for end‑users
Unlimited warranty period
Explanation - CE marking requires proof that the device meets applicable EU standards, such as IEC 60601‑1 for safety.
Correct answer is: Demonstration of conformity with the relevant EU harmonized standards
Q.93 Which of the following best defines ‘accuracy’ in the context of a calibrated sensor?
The speed at which the sensor provides measurements
The closeness of the sensor’s output to the true value
The number of digits displayed on the sensor’s screen
The sensor’s resistance to physical shock
Explanation - Accuracy reflects how near the measured value is to the actual reference value.
Correct answer is: The closeness of the sensor’s output to the true value
Q.94 Which standard specifically addresses the safety of medical electrical equipment used for diagnostic imaging?
IEC 60601‑2‑33
ISO 9001
IEC 60601‑1‑2
ISO 14971
Explanation - IEC 60601‑2‑33 provides safety requirements for equipment used in magnetic resonance imaging (MRI) and other diagnostic imaging modalities.
Correct answer is: IEC 60601‑2‑33
Q.95 A device’s calibration certificate includes a ‘temperature correction factor’. Why is this factor important?
It changes the device’s color scheme
It adjusts measurement results to account for temperature‑dependent variations
It reduces the device’s power consumption
It extends the device’s warranty
Explanation - Temperature can affect sensor behavior; a correction factor compensates for these effects, improving accuracy.
Correct answer is: It adjusts measurement results to account for temperature‑dependent variations
Q.96 Which of the following is the most appropriate action if a medical device fails the IEC 60601‑1 safety test for ‘protective earth continuity’?
Continue using the device as normal
Replace or repair the protective earth connection before further use
Ignore the test result and proceed with patient use
Only replace the device’s battery
Explanation - A failed protective earth continuity test poses a shock risk; the device must be corrected before patient use.
Correct answer is: Replace or repair the protective earth connection before further use
Q.97 Which of the following best describes the term ‘repeatability’?
The degree to which repeated measurements under unchanged conditions produce the same results
The speed at which measurements are taken
The maximum temperature the device can operate at
The device’s visual appearance
Explanation - Repeatability is a measure of consistency when the same conditions are maintained.
Correct answer is: The degree to which repeated measurements under unchanged conditions produce the same results
Q.98 Which of the following is a key requirement of ISO 14971 for medical device manufacturers?
Implementing a documented risk management process throughout the product lifecycle
Ensuring the device is waterproof
Providing free software updates for life
Limiting device use to a single country
Explanation - ISO 14971 mandates a systematic risk management process from design through post‑market activities.
Correct answer is: Implementing a documented risk management process throughout the product lifecycle
Q.99 When calibrating a blood glucose meter, which of the following reference materials should be used?
A certified glucose solution with traceable concentration
Distilled water
A saline solution
A standard voltage reference
Explanation - A certified glucose solution provides a known concentration for accurate calibration of glucose meters.
Correct answer is: A certified glucose solution with traceable concentration
Q.100 Which standard addresses the software life‑cycle processes for medical device software?
IEC 62304
ISO 9001
IEC 60601‑1
ISO 14971
Explanation - IEC 62304 defines requirements for the development and maintenance of medical device software.
Correct answer is: IEC 62304
Q.101 A medical device is to be used in a home environment. Which additional standard should be consulted beyond IEC 60601‑1?
IEC 60601‑1‑11
ISO 14001
IEEE 802.15.4
ISO 45001
Explanation - IEC 60601‑1‑11 provides specific safety and performance requirements for medical devices used in the home.
Correct answer is: IEC 60601‑1‑11
Q.102 Which of the following best defines ‘linearity error’?
A constant offset across the measurement range
A deviation that varies proportionally with the input value
Random fluctuations around the true value
A delay in sensor response
Explanation - Linearity error reflects how the sensor’s output deviates from a straight line across its range.
Correct answer is: A deviation that varies proportionally with the input value
Q.103 What is the main purpose of a ‘post‑market surveillance’ program for biomedical devices?
To monitor device performance and safety after it has been released to the market
To increase the device’s price
To redesign the device’s packaging
To limit the number of devices sold
Explanation - Post‑market surveillance gathers real‑world data to identify any emerging safety issues or performance trends.
Correct answer is: To monitor device performance and safety after it has been released to the market
Q.104 Which of the following is a typical tolerance for the accuracy of a clinical‑grade ECG machine?
±0.1 mV
±10 mV
±5 % of the full‑scale range
±0.5 % of the measured value
Explanation - Clinical ECG machines generally require accuracy within about 5 % of the full‑scale voltage range.
Correct answer is: ±5 % of the full‑scale range
Q.105 Which of the following best describes a ‘protective earth (PE) fault indicator’ in a medical device?
A visual or audible alarm that signals loss of protective earth continuity
A feature that increases battery life
A component that changes the device’s color
A software update mechanism
Explanation - A PE fault indicator alerts users when the safety grounding path is compromised, prompting corrective action.
Correct answer is: A visual or audible alarm that signals loss of protective earth continuity
Q.106 Which of the following is a common cause of drift in a calibrated sensor over time?
A change in ambient temperature
Improper storage conditions
Battery voltage fluctuations
Software updates
Explanation - Exposure to humidity, temperature extremes, or mechanical stress can cause sensor drift over time.
Correct answer is: Improper storage conditions
Q.107 Which standard focuses on the risk management process for medical devices?
ISO 14971
ISO 9001
IEC 60601‑1‑2
ISO 13485
Explanation - ISO 14971 provides a framework for identifying, evaluating, and controlling risks associated with medical devices.
Correct answer is: ISO 14971
Q.108 A calibrated pressure transducer shows a non‑linear response at low pressures. Which calibration strategy can best correct this issue?
Increase the device’s voltage supply
Add more calibration points in the low‑pressure region and fit a polynomial curve
Reduce the sampling rate
Replace the device’s power cord
Explanation - Additional low‑pressure calibration points enable a more accurate correction of non‑linear behavior.
Correct answer is: Add more calibration points in the low‑pressure region and fit a polynomial curve
Q.109 Which of the following is a key element of a calibration report?
Device serial number and model
User’s favorite color
Company’s marketing slogan
Number of devices sold
Explanation - A calibration report must identify the instrument being calibrated, including its serial number and model.
Correct answer is: Device serial number and model
Q.110 What is the primary benefit of using ‘automatic calibration’ features in modern biomedical instruments?
Reduces human error and ensures consistent calibration procedures
Increases the device’s physical size
Requires no reference standards
Eliminates the need for any maintenance
Explanation - Automatic calibration automates adjustments, improving repeatability and reducing operator‑induced errors.
Correct answer is: Reduces human error and ensures consistent calibration procedures
Q.111 Which of the following best defines ‘specific absorption rate (SAR)’?
The rate at which a device consumes power
The rate at which energy is absorbed by human tissue from an electromagnetic field
The speed of data transmission
The pressure exerted by a device on the skin
Explanation - SAR measures the exposure level of tissue to electromagnetic energy, relevant for safety assessments.
Correct answer is: The rate at which energy is absorbed by human tissue from an electromagnetic field
Q.112 Which standard specifies the environmental testing requirements (e.g., temperature, humidity) for medical devices?
IEC 60601‑1‑11
ISO 14971
IEC 60601‑1‑2
ISO 13485
Explanation - IEC 60601‑1‑11 includes environmental requirements for devices used in home and other non‑clinical settings.
Correct answer is: IEC 60601‑1‑11
Q.113 In a calibration lab, why is it important to use reference standards that are themselves calibrated?
To ensure the reference standards are more expensive
To maintain traceability and confidence in the calibration results
To make the lab look more professional
To reduce the time needed for calibration
Explanation - Using calibrated reference standards ensures that the calibration chain is traceable to recognized standards, guaranteeing reliability.
Correct answer is: To maintain traceability and confidence in the calibration results
Q.114 Which of the following is a typical calibration frequency for a high‑precision laboratory analyzer?
Every 5 years
Every 6 months to 1 year
Every 2 weeks
Every 10 years
Explanation - High‑precision lab analyzers often require semi‑annual to annual calibrations to maintain their stringent accuracy specifications.
Correct answer is: Every 6 months to 1 year
Q.115 Which of the following best describes a ‘protective earth (PE) conductor’ in medical equipment wiring?
A conductor that carries the main power to the device
A safety ground path that limits voltage on exposed conductive parts
A data communication line
A decorative cable
Explanation - The PE conductor provides a low‑impedance path for fault currents, preventing dangerous voltages on accessible parts.
Correct answer is: A safety ground path that limits voltage on exposed conductive parts
Q.116 A medical device must comply with which standard to address both safety and electromagnetic compatibility in a single document?
IEC 60601‑1‑2
ISO 9001
ISO 14971
ISO 13485
Explanation - IEC 60601‑1‑2 integrates safety and EMC requirements for medical electrical equipment.
Correct answer is: IEC 60601‑1‑2