If you are looking for a great way to help clean the air in that you and your family breathe, you may want to consider getting one of those HEPA air cleaners . HEPA is an acronym for “high efficiency particulate air” or “high efficiency particle arresting”. Ninety nine percent of particles in the air are invisible to the naked eye.
These HEPA filters were designed in the 1940’s to remove airborne radioactive contaminants. They were commercialized in the 1950’s. Over time, the filters have become of use in various high tech industries such as hospitals, pharmaceutical processing, nuclear contamination, lead and asbestos abatement, tuberculosis wards, computer rooms and aerospace. They are useful in the prevention of spread of bacteria and viruses.
HEPA filter air cleaners are composed of fibers and are made of fiberglass. Membrane filters are designed to target larger particles. HEPA filters target smaller pollutants and pathogens. The particles are trapped in large amounts where other cleaners would simply circulate back into the air of your home. They trap small contaminants which cause problems for people who have allergies or other health problems.
The process of trapping pollutants which flow through a filter is defined in one of three ways: interception, impaction, or diffusion. Particles following a line of flow in the air stream come within one radius of a fiber and stick to it is called interception. Impaction is where larger particles follow the curve of the air stream and are forced into embedded fibers. Diffusion is a result of the collision of gas molecules by the smallest particles. It’s an enhancing mechanism. They are delayed in their path through the filter.
It is probable that a particle will be stopped by either interception or impaction. This is dominant at lower air flow velocities. Their efficiency increases over a lifetime. Filters will have a number assigned to them if they are able to trap at least 99.97 percent of particles of .3 microns. This information is printed on the filter. These filters are known as true or absolute type filters.
...
Read more...
| 
