EPA, HEPA, ULPA industrial clean room filters

HEPA filters are well known for their efficiency in air filtration. They were first put into use in the United States during World War II. The first HEPA filters were developed for the Atomic Energy Commission in the 1940s as part of the Manhattan Project to enable the filtration of radioactive pollutants, which were quite a novelty at the time.

HEPA filters are well known for their efficiency in air filtration. They were first put into use in the United States during World War II. The first HEPA filters were developed for the Atomic Energy Commission (AEC) in the 1940s as part of the Manhattan Project to enable the effective filtration of radioactive pollutants, which were quite a novelty at the time. The technology was perfected during World War II, then later it was licensed for use on a wider scale. HEPA filters were first used in hospital operating theatres, followed by production facilities requiring a totally sterile environment, such as for the manufacture of pharmaceuticals or computer components. HEPA filters are now used in all areas of industry and of life: on aeroplanes, in space technology and in households. Even some vacuum cleaners use HEPA filters nowadays.

What do HEPA filters filter?

Depending on their category, HEPA (High Efficiency Particulate Air) filters are capable of filtering 85 - 99.999995% of particles greater than 0.3 μm (3 microns) from the air that passes through them, and 100% of all particles 1 micron or more in diameter.
In order to have a basis for comparison, let’s consider the sizes of some of the contaminants commonly present in the air. The following data are in micrometres, equivalent to one millionth of a metre.

Classification of suspended particle filters

Filters used for ventilation and air filtration are generally classified according to various European standards. Filters for coarse and fine dust are classified and categorised by the EN 779 standard, with EN 1822 regulating suspended matter filters (EPA, HEPA and ULPA).

What is the structure of HEPA filters?

Most HEPA filters consist of a filter medium mounted on a frame made of a composite material or metal. This setup is practical and easy to use. The filter medium is generally a mat composed of micro glass fibres or a composite containing a similar type of glass fibre webbing.

Application of HEPA and ULPA filters

HEPA filters are used in cases where not only dust and coarse particles need to be removed from the air, but also pollen and fine particles. Depending on the grade of the filter, they can even retain bacteria and microparticles (0.4 microns), allowing them to be used safely in sterile room HVAC systems.

• clean rooms
• sterile rooms
• hospitals
• production of pharmaceuticals
• microelectronics plants

More information on » Clean room filters and HEPA filters

This news may be interesting for others. Please share it!