The HVAC system is an important part of a pharmaceutical manufacturing to maintain the required environment with desired temperature, RH, and air classification.
HVAC system Validation Tests
Air Flow Pattern or smoke pattern
- The test shall be performed in Rest as well as Dynamic condition.
- Video recording shall be performed for the airflow pattern test.
- The air should flow unidirectionally from supply towards the return air filter or grill within the room.
Frequency:
- Once in a year.
Air velocity/airflow measurement and calculation of air changes
- Calculate the ACPH is as follows:
Air changes per hour (ACPH) = Total CFM X 60
- Using Anemometer for air velocity
- The volume of the room is calculated and the air changes per hour are obtained by dividing the total air change by the volume of the room.
- A variation in air volume shall not be ±20% from the design CFM
Frequency:
- Once every six months.
- At Every Filter replacement.
Filter leak test
- For the leak test of the HEPA filter, aerosol calibrated photometer shall be used
- AHU system and the air velocity is checked at all the corners. In case it is found to exceed the upper limit, a gas cut (silicon) is used to decrease the leakage.
Note:
Earlier to carry out this test, DOP was used. But nowadays, it is replaced by the PAO (poly alpha olefin) taking into consideration the carcinogenicity of the DOP.
Frequency:
- Once every six months.
- At Every Filter replacement.
Viable monitoring (microbial monitoring) Passive /Active Air sampling
- To determine the viable particle count test by exposing the settle plate and air sampling in the defined areas.
Passive Air Sampling
- Plates shall be exposed on plate exposure stand at the pre-defined locations mentioned in individual format for each stream for not less than 4 hrs.
- Exposed plates shall be recovered after 4 hrs. of exposure and incubate at specified condition 20-25ºC for 72 hrs. Then 30-35ºC for 48 hrs.
- Plates shall be observed for any microbial growth after 5 days.
Active Air Sampling:
- The plate shall be recovered after sampling and incubate at specified conditions : 20-25ºC for 72 hrs. then 30-35ºC for 48 hrs
Frequency:
-Once in every six months for three consecutive days for ISO classes 5, 6, 7, and 8 at defined location. Continuous monitoring in critical / core areas.
Non Viable Particle count
Frequency:
- Once in every six months for three consecutive days at a defined location.
- At Every Filter replacement.
Differential pressure test
It is calculated by use of the manometer
Frequency:
For 3 days (Every six month) Continuous monitoring
Recovery study
Frequency:
- Once in a year.
Temperature and humidity control test
Frequency:
-For 3 days (Every six month) Continuous monitoring
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