HEPA Air Filters

What does HEPA stand for?

HEPA filter means “High Efficiency Particulate Air “– filter. It was first developed in the forties to be used when the atomic bomb was being assembled, it became more common after that and continued to be known with the same name.

Working of HEPA air filters?

HEPA filters are made of a dense fabric of crisscrossing fibers that trap particles in the air.It is capable of trapping those particles by 3 different mechanisms – interception,impaction,and diffusion - and not only by acting as a sieve.

What is the benefit of HEPA filters?

They can reach 99% filtering, they are used to filter air used to ventilate places where a high quality of air cleanness is desired, like in industrial plants for delicate material, in medical and biological industry etc. and in HOMES, especially homes of allergy sufferers, where these filters help the allergic people by removing pollen, mold spores, and dust mite droppings.

Problems with HEPA filters:

1. Although they do not cost much upfront, they need to be replaced periodically because they cannot be opened and cleaned.
2. Large units can only cover a single room, because of the fact that all the air is forced through the filter,only little will come out the other side.
   
3. They do not improve odors or remove fumes.They have little effect on microorganisms.
   
4. Noise pollution.

HEPA filters in vacuum cleaners:

Many vacuum cleaners are fitted with a filter that purifies the air coming out of the vacuum cleaner’s bag. This is especially useful for asthmatic people and allergy sufferers.