Maintaining a cleanroom is essential for industries that require high levels of product quality and safety.

However, it can be challenging to maintain a cleanroom environment free from contaminants. 

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In this blog post, we’ll discuss the most common cleanroom contaminants and provide practical tips to avoid them.

But first, let’s answer some common cleanroom contamination questions.

How Often Should I Clean My Cleanroom?

The frequency of cleanroom cleaning will depend on the specific needs of your facility. However, it’s generally recommended that cleanrooms be cleaned on a regular basis (we recommend a daily dry mop and a weekly wet mop), with high-touch surfaces and critical equipment being cleaned more frequently.

Some facilities opt for a continuous monitoring and logging solution in order to verify that the room never leaves its cleanliness spec.

How Do I Know If My Cleanroom Is Properly Filtered?

You can test the air and surface quality in your cleanroom to determine if it is properly filtered. Regular testing and monitoring can help ensure that your cleanroom is operating at peak efficiency and safety.

You can test the air contamination levels during routine service calls, which Vernick provides, and room re-certification provided by a third-party service.


What Should I Do If I Suspect Cleanroom Contamination?

If you suspect cleanroom contaminants are present, it’s important to take immediate action. This may include stopping production, isolating the affected area, and conducting a thorough investigation to determine the source of the contamination.

Okay, let’s move into the most common cleanroom contaminants.

Particulate Matter

Particulate matter refers to tiny particles that are present in the air and on surfaces. 

Sources of particulate matter that are considered cleanroom contaminants include human skin cells, dust, and fibers from clothing or equipment. 

The amount of allowable particulate matter in your room depends on the ISO classification of your room. 

For example, an ISO 8 room can allow 3,520,000 particles/cubic meter, while an ISO 5 room only allows 3,520 particles/cubic meter. 

These terms are interchangeable with the Federal Classification FS209E, Class 100,000 and Class 100, which allow for 100,000 particles/cubic foot and 100 particles/cubic foot, respectively.

To make it a bit simpler, check out this chart on ISO classifications.


These contaminants can affect the performance of cleanroom equipment and products. To avoid particulate matter contamination, consider the following tips:

Regularly Clean Surfaces and Equipment

This ensures that if particulates do enter the room, they don’t stick around long. You would typically do this on a regular, planned out schedule.

Implement Proper Gowning Procedures

Gowning properly makes sure that the particulate that resides on your clothing doesn’t make it inside the room. Those working in a cleanroom would gown up in an ante-room.

Gowning procedure depends on the industry, but can include (but is not limited to) bunny suits, hairnets, glasses, masks and shoe covers.

Ante-rooms typically have a sink for washing, as well as sticky mats to pick up any material remaining on the operator’s shoes.

Use HEPA Filters

HEPA filters are so important that we wrote an entire blog on it. HEPA filters are the best line of defense for air circulating in the room.

CMM Room HEPA Filters


Microorganisms, also known as viables, include bacteria and fungi that can cause contamination in cleanrooms. These are of particular concern in pharmaceutical and bio science environments. 

They can spread through the air, on surfaces, and on personnel. 

To avoid microorganism contamination, consider the following tips:

Proper Hand Hygiene Procedures

Regularly washing your hands with the proper soap and water eliminates almost all of the microorganisms that may be present on your hands.

Clean Surfaces and Equipment

Just like hands, the tools you use during your process may collect unwanted contaminants. To eliminate them, follow a similar disinfectant procedure as washing your hands.

Specific anti-bacterial and fungicidal solutions may be used depending on the end user’s process.

Chemical Contaminants

Chemical contaminants refer to chemicals that are considered cleanroom contaminants 

Sources of chemical cleanroom contaminants include cleaning agents, lubricants, and oils and greases, and process related chemicals that are commonly found in the manufacturing processes that require a cleanroom.

How to use a cleanroom

Chemical contaminants can have adverse effects on product quality and safety. 

To avoid chemical contamination, consider the following tips:

Use Approved Lubricants and Cleaning Agents

Pay special attention to labels, and make sure you don’t use any old lubricant.

Store Chemicals Properly

If chemicals are stored improperly, they can acquire particulates if the space they’re housed in is unclean.

Inspect Leak-Prone Equipment

Make sure that your tools are operating effectively.

Create Dedicated Exhaust Systems

Certain chemicals require a dedicated exhaust system due to their hazardous nature such as in a USP-800 hazardous compounding cleanroom. This would include a biological safety cabinet, and a high-plume laboratory exhaust fan.

using gloves in a cleanroom

Other Common Cleanroom Contaminants

In addition to the contaminants listed above, other common contaminants that are found in cleanrooms include pollen, human skin cells, and residues. 

Much like the other sources of contamination, these sources can be prevented easily. 

To avoid contamination from these cleanroom contaminants, consider the following tips:

  • Implement strict gowning procedures for personnel
  • Use sticky mats or flooring to trap particles and contaminants
  • Regularly clean and disinfect surfaces and equipment


Maintaining a cleanroom environment is essential for industries that require high levels of product quality and safety. 

By understanding the most common cleanroom contaminants and implementing proper contamination prevention techniques, you can ensure that your cleanroom operates at peak efficiency and safety.

If you want more in-depth information on how to prevent contamination, be sure to check out our blog on 3 key ways to prevent cleanroom contamination.

If you need help with cleanroom maintenance, contact our team.

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What Are The Most Common Cleanroom Contaminants?

The most common cleanroom contaminants include particulate matter (such as dust and fibers), microorganisms (such as bacteria and fungi), chemical contaminants (such as cleaning agents and lubricants), and other contaminants (such as pollen and human skin cells).

Why Are Cleanrooms Important?

Cleanrooms are important because they provide a controlled environment that is free from contaminants. This is essential for industries that require high levels of product quality and safety.

How Does Particulate Matter Effect Cleanrooms?

Particulate matter can affect the performance of cleanroom equipment and products. They can also be a source of contamination if they are not properly controlled.

How Do Microorganisms Effect Cleanrooms?

Microorganisms can cause contamination in cleanrooms, which can affect product quality and safety. They can spread through the air, on surfaces, and on personnel.

How Do Chemical Contaminants Effect Cleanrooms?

Chemical contaminants can have adverse effects on product quality and safety. They can also damage cleanroom equipment and affect the performance of cleanroom products.

How Can You Avoid Cleanroom Contaminants?

Strategies for avoiding cleanroom contamination include implementing proper hand hygiene procedures, regularly cleaning and disinfecting surfaces and equipment, and using HEPA filters to filter out contaminants.

How Do I Choose The Right Cleaning Agent For My Cleanroom?

When choosing a cleaning agent for your cleanroom, it’s important to select one that is approved for use in cleanrooms. You should also consider the type of surface you will be cleaning and any specific cleaning requirements.