Mechanical Engineering Role in Cleanroom Construction

Mechanical engineering is one of the most important segments of cleanroom construction. During cleanroom design, it is important to install an appropriate sized air conditioner to keep the entire environment cool. It is also crucial to design a perfect airflow and filtration system of the cleanroom to achieve the desired result. Mechanical engineers also assist in calculating the columns, beams, walls and other seismic bracing of the cleanroom design during its construction.

Mechanical engineers’ role in cleanroom construction

Mechanical engineering helps in creating the following components of the cleanroom design.

• HVAC system

Mechanical engineering helps in designing the HVAC cooling system for the cleanroom. The engineers take into account different segments to appropriately estimate the cooling size of the ACs. The factors include classification and size of the cleanroom, exhaust CFM, total number of working personnel in the facility, heat load of the filtration system, lighting and procedures, surrounding warehouse temperature, make-up air and many more.

Mechanical engineers are also responsible to select between chilled water and DX of the HVAC systems during cleanroom design. It helps in efficiently achieving the humidity and temperature requirements of the cleanroom. For tight humidity and temperature necessities, they often implement dedicated air handlers for every room with cold and hot water coils. Mechanical engineers also separate the dehumidifier and humidifier systems from the HVAC for maintaining the necessary humidity.

• Air flow

Mechanical engineers must also determine the fan location of the HEPA filters to make sure there are no dead spots in every cleanroom. The return air wall locations are also equally significant in the cleanroom construction, as the air flow coming out from the fan of the HEPA filters present in the ceiling will return because of the lower walls. In the case of a class 100 cleanroom, which is one of the most demanding designs, mechanical engineers might select to raise the floor to return the air to the closest laminar airflow.

• Filtration

Mechanical engineering plays a major responsibility in selecting the HEPA filtration system type. There are two types of HEPA filters: DCM (Ducted Ceiling Modules) or HEPA filter units with fans for decontaminating the air. HEPA filters with fans are usually present in the negative pressure zone just above the ceiling in the cleanroom construction. DCM includes filters only, which need customized air handlers for driving the air through the filters at the necessary rate.

The engineers also decide the total number of HEPA filters necessary for achieving the required air changes every hour for achieving the desired environment for the cleanrooms. For class 100 or ISO-5 cleanrooms, mechanical engineers choose ULPA filters in place of HEPA ones. Although HEPA filter sare the most commonly implemented systems for cleanrooms, ULPA filters are superior to them.

It allows a lower number of air particles to pass through the filters as they trap even the tiniest particles. ULPA filters catch nearly 99.99% of air particles at 0.12u in comparison to the HEPA filters, which capture 99.97% at 0.3u. ULPA filters are more effective in capturing the air particulates, but cost more than the HEPA filters. Since they are less sustainable in comparison to HEPA filters, engineers use them only in the highest cleanroom construction classification.

• Structure

A structural mechanical engineer also has to do the basic calculations of the cleanroom designs. It includes calculations for beams and columns, building permits, seismic bracing, footings and others.

FAQ

What things should you never take into a cleanroom to avoid contamination?

Cleanroom personnel are never allowed to bring cigarettes, food and drink, chewing gum, open notebooks made of paper, cardboard, pencils, and sandals or shoes inside a cleanroom. All these articles increase the chances of contamination inside the cleanroom.

End words

Mechanical engineering has a key role in the cleanroom construction. The engineers are involved in designing the HVAC system, including structural, airflow and filtration engineering. HVAC systems help to keep the surroundings of the cleanroom cool. Airflow and filtration systems ensure that the cleanroom has all the desired components necessary for manufacturing the final product. Mechanical engineers have all the structural integrations necessary for meeting the infrastructure code and making sure that the cleanroom construction supports all the equipment.