In scientific, pharmaceutical and clinical applications, it’s essential to have spaces free of bacteria or micro-organisms that could contaminate the workspace. Vertical/horizontal laminar flow hoods are the answer.
Laminar Flow Hoods
are the tools you need to create a safe, sterile zone for all laboratory requirements. They can be either horizontal or vertical. Essentially, this is a space which, thanks to specific air treatment, enables work to be carried out in an area strictly controlled by non-road particles. This type of equipment is used for certain processes where pollution control needs to be reinforced
Normally, these systems are used for microbiological control procedures, packaging, sterile filling, etc., but under no circumstances should they be used for processes involving known or unknown strains of biological contaminants. For these cases, biosafety cabinets are available, designed to protect the product/process, the operator and the environment. To understand the purpose of laminar flow equipment, we need to consider how it works, and the physical space in which it will be placed.
First of all, we need to consider that extremely clean areas will be required whenever working with products or processes with requirements for a certain degree of sterility. These areas are made up of systems operating according to a laminar flow pattern.
How is laminar flow generated?
Laminarity is generated by a constant velocity in the air outlet, which homogenizes distribution in the workplace. This is made possible by the installation of HEPA filters as a prerequisite to the air outlet. However, to envisage a complete room with such filters would be extremely costly, and the question we need to ask ourselves is whether we really need the entire surface covered by HEPA filters. Although these systems may differ in certain construction features, maintaining a constant laminar airflow is essential to the objective. We could therefore reduce the requirement to a clean or ultra-clean zone, rather than thinking of the whole area in this condition.
There are two main sources of pollution in an area requiring specific control, and these can be external (linked to the environment), and internal (produced in the area either by personnel or the type of work). In the case of the former, pollution reduction is achieved by the various filtering stages through which the air must pass from the outside to reach the environment. In the case of the latter, we need to work on strict procedures, both for the running of the activity and for cleaning, including consideration of possible events.
Laminar flow hoods, in this case, contribute to the recirculation of clean air in the environment in which they are located, since they work continuously to renew the air. Let’s not forget that they take it from their environment, filter it and return it to the environment with an additional step of absolute filtration, and this process is constant.
In the case of laminar flow hoods, the continuous, evenly distributed air outlet velocity through HEPA filters moves the particles generated in the work area, causing a sweeping effect outwards from this area. This mechanism results in a Grade A workspace with a very low number of particles of various sizes.
Now, if we understand that the laminar flow system provides us with a working area free of polluting particles, that the site environment will also benefit from continuous use, as much as the use of a controlled environment will be advantageous to the operation of the system, we can consider that very often the failures associated with the operation of equipment are due to the way in which it is used. A laminar flow hood is not a piece of storage furniture, nor a desk, nor a waste receptacle, but a critical working tool, so it’s important to provide the appropriate care and maintenance to enable you to work with consistent results throughout your life.
