QHSE DOCUMENTS-RISK ASSESSMENT FOR HVAC SYSTEM

For the risk assessment of HVAC, uploaded by QHSE Documents, various methods and concepts can be used, here you can use Failure Mode Effect Analysis (FMEA) concepts for an HVAC system The HVAC is the “Direct Impact” system in the aseptic practice which directly affects product quality and regulatory compliance. The level of risk associated with the HVAC system can be assessed based on the impact and severity of the probable risk in aseptic practice in manufacturing units, particularly in the pharmaceutical sector. On completion of the risk assessment, control and measures must be developed and recommended actions for unacceptable risk will be identified for improved Current Good Manufacturing Practice (CGMP) Regulations compliance and qualification of the system upgrades. After completion of the risk assessment, the recommended actions must be extended and verified against the qualification stages of the HVAC system. Finally, the HVAC system should be subjected to a performance qualification (PQ) study. All the tests must be performed, and a report must be generated.

Description of Identified Risk 

1. New equipment facility or system or any “major change in the existing equipment” may affect the product requirement safety feature and environment.
2. Air/energy losses may occur during air distribution through ducts. Contamination due to air leakage when AHU is shut down. (Negative pressure may lead to contamination)
3. Installation of components at inappropriate places leads to inadequate performance of AHU.
4. Inappropriate operation of AHU may lead to non-compliance concerning performance requirements and frequent maintenance.
5. Blocking of the filter affected the differential pressure level and may lead to contamination in areas at higher cleanliness classes.
6. Uncalibrated instruments affected the monitoring and controlling of the desired product environment condition.
7. Failure of Audio/ visual indication of alarms may not alert the personnel and will continue to operate in non-complying conditions.
8. Air velocity and air changes may affect the cleanliness class, heat load and recovery from contamination.
9. Differential pressure is critical for maintaining cleanliness class and cross-contamination.
10. The validation status concerning the filter integrity may be affected.
11. Airflow patterns may affect the effective cleanliness of the area.
12. Comply with Grade A environment
13. Air cleanliness in clean rooms may affect contamination-sensitive activities.
14. Airborne particle concentration may affect the specification of air cleanliness in clean rooms.
15. The temperature may lead to product instability, personnel discomfort, and microbial growth.
16. Relative humidity may affect moisture-sensitive activity.
17. Microbial contamination leads to loss of sterility.

Likelihood of Occurrence 

1. Low-URS and vendor DQ are in place.
2. Low-Sheets are lock-forming quality: lock; Insulation; Thermocole; Cladding-aluminum
3. Low-Vendor installed component as per approved drawing.
4. Medium-Instrument is running as per the approved SOP with control parameters.
5. Low-Differential pressure monitoring switches are placed across the filter.
6. Medium-Instrument/components are identified for calibration with tag no.
7. Medium-List of all alarms is verified and classified in critical/ noncritical based on impact on product quality/purity.
8. Medium-Supply and return air volume (CFM) of AHU are as per the requirement of area and occupancy.
9. Low-DP gauge continuously monitors the pressure difference between different classrooms (one for each room separately).
10. Low-Change in the HEPA filter at regular intervals and as required.
11. Low Rooms are designed from positively to negatively pressurized zones. Dampers maintain the desired differential pressure in the room.
12. Low-The UAF unit is installed. The area under the unit should comply with class A standards/requirements.
13. Low-Final filtration of supply air in the room through terminal mounted HEPA filter (H-13) efficiency 99.97% down to 0.3-micron particles.
14. Medium-Environmental monitoring devices are in place (FMS). Final filtration of supply air in the room through terminal mounted HEPA filter.
15. Low-Temperature sensors are in each room and common return air duct.
16. Low-RH sensors are provided for the common return air duct. A dehumidifier is in place.
17. Medium-Alert and action limits are determined by trend analysis.

Risk Related to the Probability of Detection

1. High-If any mismatch observed between the user and supplier specification.
2. High-If there is no check done to verify the duct leakage.
3. High-If drawings are not available.
4. High-If the operating and maintenance personnel are not trained concerning the related SOP.
5. High-If the sensors fail to generate alarms.
6. High- If the instruments are not calibrated as per frequency.
7. High-If the alarms are not generated during the excursion in temperature/ RH/DP beyond the set limit.
8. High- If there is no check done to verify the air velocity air changes per hour (ACPH).
9. High-If differential pressure value less than alarm limit and greater than specified time between similar and non-similar classes.
10. High-If there is no check done to verify the integrity of filter.
11. High-If differential pressure value less than alarm limit and greater than specified time between similar and non-similar classes.
12. High-If the turbulence found in the air flow pattern.
13. High-If there is no check done to verify the integrity of filters.
14. High-If there is no check done to verify the integrity of filters and air velocity.
15. High-Excursion of temperature beyond the set limit due to different operations.
16. High-Excursion of RH beyond the set limit due to CIP/SIP operation.
17. High-Critical for Grade A environment.

Recommended Action

1. User and supplier specifications and drawings are evaluated for their compliance with the intended use and cGMP during DQ.
2. Duct leakage should be checked through smoke tests and reports addressed in the IQ.
3. Schematic, P&ID, and GA drawings should be verified in IQ.
4. Identify and verify the SOP during OQ.
5. DP switches are provided across the HEPA filter for monitoring the blocking of the filter and feedback given to DDC which generates an alarm.
6. Instrument/ component should be calibrated (temp., RH, DP) and report addressed in the OQ.
7. All alarms should be checked, verified, and set parameters related to the safety of the product/ person/ environment during OQ.
8. The air velocity and ACPH should be checked by an anemometer to ensure that an adequate amount of air is supplied in the room and report addressed in the PQ.
9. DP should be checked through the Magnehelic gauge to verify the capability of complete installation to maintain the specified pressure difference and report addressed in PQ.
10. The integrity should be checked through the DOP test and report addressed in the PQ.
11. Non-unidirectional air flow should be checked through the WFI fogger and report addressed in the PQ.
12. Unidirectional airflow should be checked through the WFI fogger; the airflow should have a sweeping action over and away from the product under dynamic conditions and report addressed in the PQ.
13. Airborne particle count should be checked through the particle counter to Determine the cleanliness level as per ISO standards.
14. The recovery/ decontamination rate test should be checked through the DOP test in the classified area and the recovery report addressed in the PQ.
15. The temperature should be checked through calibrated instrument and report addressed in the PQ.
16. RH should be checked through calibrated hygrometer and report addressed in the PQ.
17. The viable count should be monitored through settle plate, air sampling, swab sampling, and report addressed in the PQ.

DOWNLOAD THE FILE

RISK ASSESSMENT FOR HVAC SYSTEM