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What is a Cleanroom?

What is a cleanroom? Chances are, if you are reading this blog post, you’ve been tasked with constructing a cleanroom, or finding someone who can.

Well, you’re in luck. Keep reading this blog post to find out everything you’ll need to know about cleanrooms, and how you can have one constructed in no time.

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What is a Cleanroom?

A cleanroom is a controlled environment in which contaminants such as dust, airborne germs, and aerosol particles are filtered away to offer the cleanest possible environment. The majority of cleanrooms are employed for the production of goods like electronics, pharmaceuticals, and medical devices..

Depending on the number of particles permitted per cubic meter, a cleanroom can be categorized into various classifications based on international standards (See ISO 14644). Previously prior to a globalized standard this was done with FED209E. This is where the cross reference between ISO 1-9 and Class 1 (ISO 14644) – Class 100,000 (FED STD 209E) comes in.  Additionally, cleanrooms control parameters including humidity, temperature, pressure and personal workflow.

Now that we’ve got a broad overview of what a cleanroom is, let’s take a look at the different types of cleanrooms, how they work, what industries need a cleanroom, what components make up a cleanroom, and go into cleanroom classifications.

How Do Cleanrooms Work?

A cleanroom is designed to filter impurities and particulates from the air stream.   This is accomplished by moving air via mechanical means (fans) through a series of filters of a certain efficiency.

This efficiency of the filtration system and the air change rate of the room will determine the rooms classification. Additionally all outside or make up air to the room will pass through increasingly efficient filters.

What Types of Cleanrooms Exist?

When constructing your next cleanroom, you can choose between a standard construction cleanroom, and a modular cleanroom. Because we do a lot of work in the modular space, we’ll discuss the different modular options offered in the next few paragraphs.

The two most common types of cleanrooms that exist are hardwall and softwall. 

Check out our blog to learn more about the specific differences between a hardwall and softwall cleanroom.

Softwall Cleanrooms

Modular softwall cleanrooms are tent-like buildings that perform less effectively when compared to their hardwall counterparts. Softwall clean rooms can be built as standalone structures or hung from the ceiling of your building because they are lightweight and simple to put together. They are also conveniently moved.

Softwall Cleanroom

Hardwall Cleanrooms

A hardwall cleanroom provides the highest level of control, particularly when built with a recirculating air system rather than a single-pass system that doesn’t re-use the filtered air. The rigid walls also allow users to restrict access to the controlled environment through a designated entryway. 

Hardwall cleanrooms are prefabricated, demountable wall systems that are smooth, non-shedding, and nonporous, making them easy to clean. They also offer the advantage of being cost effective, expandable, moveable, quick to construct, high-quality, and offer tax benefits.

Hardwall Cleanroom

What Industries Need Cleanrooms?

Over the years, these industries have required a level of high quality control and regulations that only a cleanroom could provide:

  • Semiconductor
  • Microelectronics
  • Micro-Electromechanical Systems (MEMS)
  • Medical Devices
  • Precision Coating
  • Pharmaceutical
  • Injection Molding
  • Aerospace
  • Academia

Learn more about industries that require a cleanroom.

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Cleanroom Classifications

There are 9 ISO classifications of cleanrooms:

  • ISO 1

  • ISO 2

  • ISO 3 (FS 209 E class 1 equivalent)

  • ISO 4 (FS 209 E class 10 equivalent)

  • ISO 5 (FS 209 E class 100 equivalent)

  • ISO 6 (FS 209 E class 1,000 equivalent)

  • ISO 7 (FS 209 E class 10,000 equivalent)

  • ISO 8 (FS 209 E class 100,000 equivalent)

  • ISO 9 (room air)

The cleanest room, ISO 1, is thought to include 10 or fewer particles that are.01 microns in size and 2 or fewer that are 0.2 microns in size.

For context, In a known sample of ISO 9, which is considered to be typical room air, there must be fewer than 35,200,000 0.5 micron, 8,320,000 1 micron, and 293,000 5 micron particles.

If you’re not sure what cleanroom you require, check out our blog on how to decide the cleanroom classification you need.

What Components are in a Cleanroom?

A cleanroom is divided into four zones: the exterior environment, support areas, adjacent cleanrooms, and the inner clean zones.

The external environment is where the people and the things to be worked on originate. The interior clean zones are where the job is done. But it is important to monitor the amount of particles in each zone (apart from the outer environment).

Inner Cleanroom Zone Components

Aside from air filters, ceiling systems, and lighting components, your project may also require a number of other cleanroom components. This can include laminar flow workstations, pass-thru cabinets, air showers, airborne particle counters, and vinyl curtains.


We hope the information in this blog helped to educate you on everything you’ll need to know regarding cleanrooms. If you need more specific information, be sure to check out our blog.


Need help building your next cleanroom? Contact us.