Why we have to switch on R-LAF before 15 minutes of dispensing and why it is 15 minutes.

In the Reverse Laminar Air Flow unit (RLAF), an evenly distributed Downflow of low turbulence, recirculated, HEPA Filtered clean air, draws harmful airborne dust of products/raw materials away from the operator’s breathing zone and is captured within the multi-stage onboard filtration system. The downflow air produced within the booth’s safe work zone area forces HEPA-filtered air over the operator’s head and shoulders and downward towards the low-level exhaust system. The downdraught prevents airborne dust caused by weighing and dispensing operations from rising into the operator’s breathing zone. The air forced downwards is extracted at a low level into the booth’s filtration system where dust particles are contained at each level of filtration prior to being recirculated back into the booth’s air stream. In order to stabilize this system of HEPA filtration of air in the RLAF, it is started 15 minutes before dispensing operations. There is no specific reason for 15 minutes. It is generally recommended by the manufacturers of RLAF to start the system for about 15 min before actual dispensing or sampling operations to achieve a stable state (equilibrium in air- filtration system).

thank u so much sir…