Depending on what industry you’re in, you may find yourself needing to purchase or make use of a cleanroom. A cleanroom is a sealed, controlled space where work can be carried out in controlled, contaminant-free conditions. But how do cleanrooms work? Let’s take a look.

Cleanrooms are used in two main applications:

Electronics manufacturing – Since silicon chips and other electronics components are extremely sensitive, and must conduct electricity perfectly through very small and elaborate systems, dust and other contaminants can ruin them. All computers contain parts made in cleanrooms.

Pharmaceuticals – The production of drugs, as well as other bio science research and manufacturing, must be done in totally contaminant-free environments. This ensures the purity of the substances, as well as patient safety.

Other forms of scientific research and engineering may also use cleanrooms, but these are the most common.


In order to meet the strict requirements of these industries, cleanrooms make use of a variety of technologies:

Filters for outside air – All air coming into a cleanroom must be thoroughly filtered so that it does not pass contaminants into the protected space. “Contaminants” in this context include dust and tiny particles that are common and completely safe in normal air. At a minimum, HEPA (high efficiency particulate air) filters are used; in some cases ULPA (ultra-low particulate air) filters are also used to attain the highest level of purity.

Internal recirculation filters – Air within a cleanroom can still pick up particles created by work processes, as well as from tools and furniture/fixtures. Thus, the filtered air within the room is continuously circulated through additional filters to scrub it of internal contaminants.

Climate control – Temperature and (especially) humidity can affect sensitive materials and must be controlled. Air within a cleanroom is kept at a constant temperature and normally at very low humidity levels. Ionic dehumidifiers can be used to avoid contamination from conventional dehumidifiers.

Air pressure – Some processes require positive or negative air pressure, so the pressure within the room can be controlled if needed. Additionally, positive air pressure means that particles in the entrances tend to blow away from the cleanroom and not come in with personnel.

Airlocks – All personnel enter through airlocks, multi-stage airtight sally ports. This allows unfiltered outside air to be drained from the airlock chamber and replaced with filtered “clean” air before they enter. Some airlocks use high-pressure air showers to blast particles off of personnel as they enter.

What does your company use cleanrooms for?