Usually, the word “laminar” assumes uniformity of the airflow velocity over the entire area of the allocated zone. Without a laminar device, it is very difficult to achieve uniformity of the air flow.
In situation of the absence of uniform flow, we don’t use LAMINAR word, but write Local zone class A instead.
Laminar device is made of anodized aluminum in aluminum frame with stretched fabric on it. This is a technologically developed low-pressure airway that prevents the possibility of accidental air entry into the sterile zone bypassing the filters, and reduces the unevenness of the unidirectional flow, as well as the pressure loss and noise level.
When carrying out validation work, SANBELA specialists noticed, that without laminar device, the air speed under the filters is of 0.6-0.7 m / s and the speed in the space between the filters due to turbulence is 0.1-0.15 m / s.
After installation of the laminar device, an average of 0.36-0.4 m / s was achieved on the entire isolated clean zone, thus air flow uniformity was achieved.
Theoretically, even without a laminar, at a distance of 1-1.5 meters from the inflow, the air flow can be uniform. However, if there is any furniture or equipment in the work area, the air flow will not be aligned on its own.
It is worth noting that the need for a laminar device is determined by the technology of works that are carried out in a clean room. Formally, it is needed everywhere, but somewhere its availability is not critical and somewhere it is necessary.