HEPA Air Purifiers

HEPA stands for "High Efficiency Particulate Arrestor." It is an advanced type of air filter used in air purifiers and in top-of-the-line vacuum cleaners.

Most HEPA Air Purifiers will separate out airborne particles down to 0.3 microns in size with 99.97% efficiency. They are effective in removing tiny allergens such as mold spores, dust mites, animal dander and pollen.

HEPA filtered air cleaners are used by companies who specialize in asbestos removal, and clean up of potentially deadly chemical spills. The contaminated air is circulated though the HEPA filter, which traps the miniscule particles and returns clean air back into the indoor environment.

For best efficiency the air is circulated many times through the HEPA filter to increase air quality.The higher the air exchange rate per hour, the cleaner the air will be in that room. HEPA air cleaners should service one room at a time. It is far better to have several small units - one for each room or area - than one large unit.

The best HEPA Air Purifiers will exchange the air up to 12 times per hour in a typical bedroom and up to 8 exchanges per hour in an open area or room of approximately 800 square feet. High quality units will use activated carbon or a blend of zeolite which quickly absorb and get rid of chemicals that out-gas from furniture or structural components of the home or office environment

Some HEPA air purifiers also have included a medical grade UV (ultra-violet) light system or EGF (Enhanced Germicidal Filtration) system. These systems can quickly kill bacteria, viruses and mold spores.

Most HEPA Air Purifiers will include a prefilter which will separate out the larger contaminants before the air passes through the HEPA filter. This helps prolong the life of the HEPA filter and thus reduce the operating costs.

Strengths

Removes tiny allergens such as dust mites, animal dander, mold spores and pollen.
Will remove many bacteria.
Particles are trapped in filter and not released back into the air.

Weaknesses