Critical systems audit – HVAC MCQs With Answer

Critical systems audit – HVAC MCQs With Answer

This quiz set is designed for M.Pharm students studying Audits and Regulatory Compliance, focusing on HVAC systems critical to pharmaceutical manufacturing. The questions probe design principles, validation and qualification (IQ/OQ/PQ), cleanroom classification and airflow patterns, monitoring and alarm strategies, HEPA filter integrity, differential pressure cascade, microbial and particle monitoring, maintenance, and regulatory expectations. Each MCQ reflects practical audit scenarios and regulatory thinking encountered during HVAC audits and prepares students to interpret data, identify nonconformities, and recommend corrective actions. Use these questions to solidify conceptual knowledge and to practice reasoning required for real-world HVAC compliance reviews.

Q1. What is the primary objective of an HVAC critical systems audit in a pharmaceutical facility?

• To check employee comfort and report complaints
• To ensure environmental conditions and airflow control protect product quality and meet regulatory requirements
• To evaluate energy efficiency and reduce utility costs only
• To validate manufacturing processes unrelated to air handling

Correct Answer: To ensure environmental conditions and airflow control protect product quality and meet regulatory requirements

Q2. According to EU GMP, which grade corresponds to the highest level of cleanliness for aseptic processing (local zone)?

• Grade D
• Grade C
• Grade B
• Grade A

Correct Answer: Grade A

Q3. Which airflow pattern is typically required in the critical work zone of an aseptic filling line to minimize particle contamination?

• Turbulent mixing airflow
• Bidirectional crossflow
• Unidirectional (laminar) downward or horizontal flow
• Natural convection without mechanical flow

Correct Answer: Unidirectional (laminar) downward or horizontal flow

Q4. What is the commonly specified efficiency of a HEPA filter used for sterile manufacturing at the most penetrating particle size?

• 95% at 1.0 µm
• 99.0% at 0.1 µm
• 99.97% at 0.3 µm
• 90% at 5.0 µm

Correct Answer: 99.97% at 0.3 µm

Q5. Which test is routinely used to verify the integrity of installed HEPA filters during an HVAC audit?

• Smoke visualization test only
• PAO (polyalphaolefin) aerosol challenge / DOP test (filter leak test)
• Pressure drop measurement only
• Thermal imaging scan

Correct Answer: PAO (polyalphaolefin) aerosol challenge / DOP test (filter leak test)

Q6. In a positive pressure cascade for cleanrooms, which of the following differential pressures is a typical setpoint to demonstrate correct airflow direction?

• -15 Pa (negative 15 pascals)
• 0 Pa (no differential)
• +15 Pa (positive pressure of 15 pascals)
• +100 Pa (very high positive pressure)

Correct Answer: +15 Pa (positive pressure of 15 pascals)

Q7. Which parameter is NOT normally included in routine environmental monitoring of a classified cleanroom HVAC system?

• Particle counts at defined sizes (e.g., 0.5 µm, 5.0 µm)
• Differential pressure between adjacent zones
• Microbial air and surface sampling
• pH of cleanroom surface materials

Correct Answer: pH of cleanroom surface materials

Q8. What is the correct sequential order for equipment qualification in HVAC validation?

• PQ → IQ → OQ
• OQ → PQ → IQ
• IQ → OQ → PQ
• IQ → PQ → OQ

Correct Answer: IQ → OQ → PQ

Q9. How often should HVAC critical systems be requalified in the absence of major changes, according to common GMP practice?

• Only once at installation
• At least annually and after any major change
• Every ten years without monitoring
• Monthly full requalification is mandatory

Correct Answer: At least annually and after any major change

Q10. Which item is NOT a component of a typical air handling unit (AHU) used in pharmaceutical HVAC systems?

• Blower (fan)
• HEPA filter section
• Cooling/heating coils
• Autoclave chamber

Correct Answer: Autoclave chamber

Q11. What does the term “cleanroom recovery time” refer to during HVAC audits?

• Time required to clean surfaces after a spill
• Time for particle counts to return to specified limits after a disturbance
• Time between scheduled maintenance events
• Time to replace a HEPA filter

Correct Answer: Time for particle counts to return to specified limits after a disturbance

Q12. Alarm setpoints for HVAC critical parameters should be:

• Randomly chosen by maintenance staff
• Defined in SOPs with response actions and responsible personnel
• Ignored during production runs
• Set only to allow operators to override without documentation

Correct Answer: Defined in SOPs with response actions and responsible personnel

Q13. Which document is NOT typically part of HVAC validation documentation?

• User Requirements Specification (URS)
• Design Qualification (DQ)
• IQ/OQ/PQ protocols and reports
• Long-term clinical stability data for a marketed product

Correct Answer: Long-term clinical stability data for a marketed product

Q14. Which particle sizes are commonly monitored by portable particle counters in pharmaceutical cleanrooms?

• 0.01 µm and 0.05 µm
• 0.5 µm and 5.0 µm
• 10 µm and 50 µm
• 100 µm and 500 µm

Correct Answer: 0.5 µm and 5.0 µm

Q15. During an audit, which observation would most likely indicate that a HEPA filter needs replacement?

• Decrease in room temperature by 0.5 °C
• Consistent increase in pressure drop across the filter beyond control limits
• Reduced humidity setpoint in the control panel
• Change in personnel gowning procedures

Correct Answer: Consistent increase in pressure drop across the filter beyond control limits

Q16. When should HEPA filter integrity testing be performed as part of GMP practice?

• Only after visible damage occurs
• At installation and at defined periodic intervals (e.g., annually) or after maintenance
• Never, because HEPA filters are assumed effective
• Only during product release testing

Correct Answer: At installation and at defined periodic intervals (e.g., annually) or after maintenance

Q17. Why is a differential pressure cascade used between adjacent cleanroom grades?

• To maintain equal cleanliness between rooms
• To allow air movement from less clean to more clean zones
• To prevent flow of contaminants from lower-grade to higher-grade areas by ensuring air moves from cleaner to less clean areas
• To increase HVAC energy consumption intentionally

Correct Answer: To prevent flow of contaminants from lower-grade to higher-grade areas by ensuring air moves from cleaner to less clean areas

Q18. Which risk assessment tool is commonly used to evaluate HVAC system impact on product quality during audits?

• FMEA (Failure Mode and Effects Analysis)
• Pareto chart for sales data
• Animal toxicity study
• Chromatographic method validation

Correct Answer: FMEA (Failure Mode and Effects Analysis)

Q19. Which immediate action is NOT appropriate when an environmental monitoring excursion for particle counts occurs in a Grade A zone?

• Quarantine affected product and assess impact
• Investigate root cause and review recent activities
• Document the excursion and implement corrective actions
• Ignore the excursion and continue production without investigation

Correct Answer: Ignore the excursion and continue production without investigation

Q20. Which method is commonly used to visualize and validate airflow patterns in a cleanroom during an HVAC audit?

• Smoke visualization (smoke study)
• pH indicator strips
• Microbial culture incubation only
• Vibration analysis of the floor

Correct Answer: Smoke visualization (smoke study)

Download