CleanroomsUSA

Cleanroom Components and Classification Part 1

High Efficiency Particulate Air (HEPA) Filters

The most critical component of a cleanroom is its filtration system, which starts with HEPA filters designed to remove particles as small as 0.3 μm. To be classified as a HEPA filter, it must remove 99.9% of contaminants. Typically, cleanrooms employ multiple filters, including prefilters that capture larger particulate matter before the airflow reaches the HEPA filters.

In both softwall and hardwall cleanrooms, filters are usually installed in the ceiling to facilitate a downward airflow. This setup is compatible with both recirculating and unidirectional airflow systems. A key factor in determining a cleanroom's classification is its air change rate, which can be 300 cubic feet per minute, and is dependent on the efficiency of HEPA filters.

Cleanroom Ceilings

Cleanroom ceilings consist of drop ceilings made from acoustical panels suspended on a tightly fitted grid, available exclusively in white. The height of the ceiling can vary based on room requirements. The snug fit of the tiles prevents dust, moisture, and contaminants from entering the room.

Ceiling grids, like many cleanroom components, are made from high-quality aluminum or stainless steel. Tiles installed on the grid are sealed with a gel or rubber gasket around their edges to ensure a tight fit.

Lighting in a cleanroom is often one of the last considerations in its design. While the lux level, or light intensity, is important, the lighting must not interfere with the airflow and filtration systems. LED lights are practical due to their linear shape and ability to be surface-mounted between HEPA and ULPA filters. Ideally, lighting should be placed on the roof, allowing for cleaning or replacement without compromising the cleanroom's integrity.

Manufacturers produce cleanroom ceiling tiles by cutting a large sheet of raw material into uniform shapes and sizes. Sealing material is added last before the tiles are shipped to installers. This cutting and shaping process ensures that the tiles will fit together snugly.

- - -