Clean room system in Pharmaceuticals

Introduction:

There are many criteria that should be considered while designing a clean room or clean zone. Some of the factors that tend to have impact on cleanliness of the room are building structure, air flushing rate and filtration, pressure, temperature, humidity, flow of personnel and material, gowning methods, surrounding air conditions and SOP’s.

Clean room should be classified by the manufacturer as built or at rest or operational.

Concentration of airborne particles should be determined for classification of cleanliness in clean room.

• Below table gives the maximum permissible concentration of airborne particles.

Grade A – It is considered as the zone for highly risk operations like filling and making aseptic connections. Air should be unidirectional with speed of 0.36 to 0.54 m/s at a specified test position of 15-30cm below air distributor. The velocity of air should not be less than 0.36m/s.

Grade B – it provides background environment for grade A in operations like aseptic preparation and filling.

Grade C & D – These are the clean areas meant for less critical stages of manufacturing sterile products or any other activity that doesn’t involve product directly.

Clean rooms should be classified by standards specified in ISO 14644

• Limits for Microbial contamination are specified as follows ¹:

  ¹         = average values

 ²       = settle plates may be exposed for less than 4hours

CFU = colony forming units

• To verify contamination due to particles and microbes and various components of air in a cleanroom various tests can be conducted.

• Particle count test
• Air pressure difference
• Airflow volume
• Airflow velocity
• Filter leakage tests
• Recovery
• Airflow visualization
• Containment leakage

Clean room, microbial contamination, airflow, air pressure

• supplementary guidelines on good manufacturing practices for heating, ventilation and airconditioning systems for non-sterile pharmaceutical dosage forms. who. http://apps.who.int/prequal/info_general/documents/trs961/trs961_annex5.pdf. published 2011. accessed 2016.
• who good manufacturing practices for sterile pharmaceutical products. who. http://apps.who.int/prequal/info_general/documents/trs961/trs961_annex6.pdf. published 2011. accessed 2016.