Airlock helps to protect the classified area from the contamination that may occur during the entry and exit of personnel and material.
Airlocks are closed rooms having two or more doors between two different controlled areas having different cleanliness levels as class B and class C, class C and class D areas. These airlocks prevent the direct airflow between these areas during the entry of material or personnel. Airlocks are called PAL (Personnel Air Lock) when used for personnel and MAL (Material Air Lock) when used for transferring the material.
There are three types of airlocks:
A. Cascade Airlock
B. Bubble Airlock
C. Sink Airlock
A. Cascade Airlock: These airlocks are very common having a higher pressure on one side and lower pressure on another side. This prevents to enter dust and contaminants from outside to airlock and from airlock to inner side.
B. Bubble Airlock: These types of airlocks have a higher pressure inside the airlock and lower pressure in both outsides. This prevents the flow of air between two areas through the airlock creating a pressure barrier.
C. Sink Airlock: Airlocks having lower pressure inside the airlock and higher pressure on both sides of the airlock. This airlock pulls air from both adjacent areas creating a low-pressure barrier.
Doors of the airlocks should open to higher pressure side; it will help to close the door. An interlocking system should be provided to prevent the opening of both doors at a time. An alarm should be provided to indicate that one door is opened.
Airlocks should be kept empty, material such as garments, shoes covers etc. should not kept in the airlocks. I have observed it many times in pharmaceuticals keeping these articles in airlocks.
Also see: HEPA Filters Used in Pharmaceuticals
Pressure different between airlock and adjacent rooms for certain production rooms must not be 20 pascal. As long as there is a pressure different and can be verified with air pattern monitoring using smoke generator, plus discipline (written in SOP)among the people who use Airlock.
ReplyDeleteis it free to use any type for any design or there is special requirement for each type of air lock ??
ReplyDeletepurpose is to control entry of air from uncontrolled to controlled areas. we can use any type suitable to the plant design
ReplyDeleteWhat is buffer area.why threebuffers are needed in pharmaceutical lab
ReplyDeletePlease visit following article
Deletehttp://www.pharmaguideline.com/2013/09/buffer-area-sterile-manufacturing-compounding-area.html
In sink air lock what is the differential pressure maintain in both adjucent room
ReplyDeleteGiven in figure. Please check.
DeleteSome non-betalactam solid dosage form plants have PAL& MAL in all process rooms .although all products are not potent products.
ReplyDeleteIn outherside some plants doesn't apply this approach .all process rooms without any PAL or MAL.
And others Only use one Air lock in each process room .
What is the difference between these philosophies.
How to select airlock? Any different application for all airlock room?
ReplyDeleteTest Comment
ReplyDeleteWhat is the maximum time for closing air lock door
ReplyDeleteIs passbox mandatory for material movement in all manufacturing departments or it can be sent through the door
ReplyDeleteYes, pass box is mandatory.
Delete