Laminars and laminar boxes. Laminar cabinets.

Laminars flow are used in clean rooms for additional air post-purification and supplying it directly to critical areas, where products or processes are open to the influence of contamination. The use of such laminar flow boxes is widespread in cleanrooms with turbulent air flow.

The use of a laminar flow box ensures that high quality air is supplied only to the places where it is needed, with significant cost savings compared to cleanrooms with unidirectional airflow throughout the space. There are many types of unidirectional flow laminators, the dimensions of which may vary depending on the dimensions of the process equipment. In most cases, installations with a vertical direction of fresh air movement are used.

The principle of operation of laminar flow hoods is as follows: fans, which are installed inside the case, pump purified air from the clean room into the chamber above the fine air filters, in which excess pressure is created, as a result, the air, when passing through the fine filters, is additionally cleaned and evenly distributed over the entire plane of the working area using a distribution grid. This distribution grille creates a unidirectional vertical or horizontal laminar air flow.

For the correct selection of the installation, it is necessary to clearly understand what production area it will serve. The area is the main indicator that affects the cost side of installing laminar machines.

Sometimes so-called local mini-zones are used in clean rooms. In mini-zones, a physical barrier (glass or plastic sheeting) is used to isolate the critical production process, and a high quality air supply is also provided. At the end of the room space, the air may be of lower quality.

Laminar flow is an even, unidirectional flow of ultrapure filtered air at a constant speed of 0.45 ± 0.1 m / s throughout a clean work area.

The term laminar flow refers to gas flow without turbulence. The air flows in parallel layers without interruption between them. Using a difficult system of fans, filters and specially designed ducting systems, we create an airflow throughout the workspace that replace particulate air without mixing with it. This is also called displacement ventilation.

The air speed is so low that you can focus on your work without worry. This became possible thanks to the layered air movement – laminar flow. With our systems, we create ultra-pure filtered air and enable an ISO class 5 cleanroom across the entire work area.

The essential part of Laminar Flow equipment is the HEPA* filter which removes minute particles (aerosols) and microorganisms and cleans the air. Laminars can be divided into vertical airflow and horizontal airflow laminars. They have a built-in airflow measurement system that alerts the worker if the airflow is disturbed. A Laminar Hood is made up of stainless steel, avoiding joints and corners to prevent the accumulation of bacterial spores. Laminar flow cabinets also have built-in UV lamps used to sterilize the cabinet before and after work.

Various operating theater ventilatory systems have been developed to prevent direct airborne bacterial inoculation of the surgical wound. Laminar air flow uses positive pressure air currents through filtration units to direct air streams away from the operative field in order to create an ultraclean zone around the operative site.

Early studies reported lower infection rates with laminar air flow and therefore it became the accepted standard for implant-related surgery. However, more recent evidence has questioned its clinical importance. The purpose of this article is to review contemporary laminar air flow handling systems and the current evidence behind their use.