All Details About the Vertical Laminar Flow Hoods
A vertical laminar flow hood allows manipulations to be carried out under sterile conditions. They are very useful for preparing culture media, inoculating a substrate, making a spore syringe or any other manipulation requiring maximum sterility. The laminar flow hoods are primarily used by laboratories and are very expensive.
In the universe and more precisely in the workspaces, many microbes circulate. However, the products produced must be protected from these harmful particles. It is for this reason that the products must be handled in sterile conditions in order to properly fight against the risks of cross- contamination. Thus, your product is protected from external contaminations. To achieve this feat, you need a laminar flow hood. But, what is a laminar flow hood really? This article sheds light on the issue. Here are the most essential matters that you will need to know about vertical laminar.
Laminar Flow Hood, what is it?
What is a Hood
A vertical laminar flow hood is a countertop that prevents contamination of harmful particles and vapors from the products being handled. As a result, the manipulations are carried out under sterile conditions and the products are protected from microbial contamination of biological samples. The laminar flow hood is mainly used for preparing culture media and also for inoculating a substrate. In addition, this work plan makes it possible to manufacture a spore syringe and to do all the manipulations requiring a more sterilized space. These laminar flow hoods are often found in laboratories.
How a Laminar Flow Hood Works
The Vertical Laminar Flow Hoods are made to create a work surface free of particles. They bring in the air through a very efficient filtration system and evacuate the air through the work surface in the unidirectional air flow. Concretely, the ambient air is sucked in by a turbine before passing through a HEPA filter to finally come to the workspace. Once the filter has been passed through, the air no longer contains particles which may be dust, yeast, bacteria or spores. Therefore, the air is seen as sterile. The laminar air flow therefore purifies the air preventing its particles from attacking your crops.
The vertical laminar flow hoods are mostly equipped with a UV-C lamp effect germicide to sterilize the work plan and its content. You must turn off the said lamp when you are working under the hood so as not to be a victim of cataracts or skin cancer. However, before proceeding to use the hood, you must sterilize your hands and all of your instruments so as not to contaminate your culture. Also avoid as much as you can to store objects on the worktop of the hood to promote sterilization.
What to choose between horizontal and vertical laminar flow?
Choosing the Right Hood
The vertical or horizontal laminar flows make it possible to effectively protect the products against the particles. With the horizontal laminar flow, the particles are completely evacuated without there being any turbulence on the work surface. Thus, the samples placed on the work area can no longer be contaminated. Also, the bottom of the hood is well sterilized by the unidirectional air flow which evacuates the particles to the outside. The vertical laminar flow helps ensure desired air quality over the entire work surface. It also evacuates particles, but turbulence can be noticed in the area of the worktop. The desired efficiency here is for the whole volume, therefore taking into account the width, depth and height.
Principle of Operation:
Ambient air is drawn in by a turbine (powerful fan) then passes through a HEPA filter before reaching the work surface. After passing through the filter, the air contains (almost) no more particles (dust, bacteria, yeasts, spores) and is considered sterile. This laminar air flow prevents any particles in the air from contaminating your crops. You must still take care to control the other vectors of contamination (your hands, instruments, etc.). Some hoods are equipped with germicidal UV lamps to sterilize the work surface.
In a future article we will try to put together some information to provide you with a guide to making a laminar flow hood.
But be aware that a laminar flow hood consists of two main parts:
- A HEPA filter: The acronym HEPA stands for High Efficiency Particulate Air or High Efficiency on Airborne Particles.
- A turbine: It is a powerful fan which draws in the outside air and “blows” it through the HEPA filter.
- A pre-filter can also be used to prevent the HEPA filter from clogging up too quickly.