The cleanest clean room on earth?

Today I had a conversation with a clean room specialist. I demonstrated our air filtration technology to him, proving the 99.999% removal of ultra-fine dust – 1 nanometer in diameter – from dirty air in only one take (so no recirculation). He then told me that the current air filter units – equipped with a.o. HEPA or ULPA filters – are adequate, so there is no need for our technology. I was surprised about his lack of curiosity.

In this article, I will give a short introduction into clean rooms, the different levels of cleanliness and the factors affecting the TCO. Finally, I challenge everyone in the industry to test our technology.

  1. What is a clean room?
  2. Are all clean rooms equal?
  3. What are the Total Cost of Ownership
  4. Why settle for less if you can if you can implement a 1-nano-filtration-unit?
  5. Contact me.

What is a clean room?

A clean room is a controlled environment typically used in scientific research, manufacturing, or other industries where contamination could adversely affect the processes or products being produced. Clean rooms are designed to minimize airborne particles, such as dust, microbes, and other contaminants, to specific levels.

Key features of a clean room include:

Air filtration:
Clean rooms use high-efficiency particulate air (HEPA) filters or ultra-low penetration air (ULPA) filters to remove particles from the air. These filters trap particles down to a specified size, ensuring the air inside the clean room remains clean.

Positive pressure:
Clean rooms often maintain a higher air pressure than the surrounding areas to prevent contamination from entering. This means that air flows out of the clean room into adjacent areas, keeping contaminants from infiltrating the controlled environment.

Controlled access:
Access to clean rooms is usually restricted and controlled. People entering the clean room typically have to wear specialized clothing, such as clean room suits, gloves, masks, and shoe covers, to prevent introducing contaminants.

Regular cleaning and maintenance:
Clean rooms require regular cleaning and maintenance to ensure that they continue to meet cleanliness standards. This may include cleaning surfaces, replacing filters, and monitoring air quality.

Clean rooms are used in various industries, including semiconductor manufacturing, pharmaceuticals, biotechnology, aerospace, and healthcare, where even tiny particles or microbes could compromise the quality of products or research.

Are all clean rooms equal?

Clean rooms are classified into different levels based on the maximum allowable concentration of airborne particles per cubic meter of air. These classifications are typically defined by international standards such as ISO, national standards or company set standards like ASML in The Netherlands. The latter, for example, is at a higher level than the ISO class 1 standard.

The classification system assigns a cleanliness level to each clean room based on the size and amount of particles allowed per cubic meter of air. ISO has classified cleanliness into 9 levels.

ISO Class 1 represents the cleanest environment with the strictest particle limits, while ISO Class 9 is the least stringent. Each class has a maximum allowable concentration of particles of specific sizes per cubic meter of air.

The choice of clean room classification depends on the specific requirements of the industry or application. Industries with stringent cleanliness requirements, such as semiconductor manufacturing or pharmaceutical production, typically operate clean rooms with higher classification levels, while less critical applications may use lower classification levels.

Total cost of ownership of a clean room

Clean rooms can be expensive to build, operate, and maintain, primarily due to the specialized equipment, materials, and procedures required to maintain the controlled environment. Several factors contribute to the overall cost:

Design and Construction:
Designing and constructing a clean room involves careful planning to meet the cleanliness standards required for the intended use. Factors such as size, layout, HVAC-systems, filtration systems, and materials used for walls, floors, and ceilings all have an impact on cost. The more stringent the cleanliness requirements, the more elaborate and therefor costly the design and construction process will be.

Clean rooms require sophisticated HVAC systems to control temperature, humidity and air pressure. Obviously, these systems will also have to filter and circulate air to maintain a certain level of cleanliness. These systems often involve HEPA or ULPA filters.

Filtration Systems:
High-efficiency air filtration systems, including HEPA and ULPA filters, are essential for removing airborne particles and maintaining cleanliness. These filters need regular replacement to ensure effectiveness, adding to operating costs. The amount and quality of the filters and the number of times you need to change the filters affect the costs.

Clean room equipment and furniture:
Clean rooms require specialized equipment and furniture designed to minimize particle generation and facilitate cleanliness. This includes items such as clean room suits, gloves, masks, furniture with smooth surfaces, and equipment enclosures designed for clean room use.

Operating and maintenance costs:
Operating and maintaining a clean room involves ongoing expenses for utilities, cleaning supplies, regular maintenance of equipment and HVAC systems, and periodic testing and certification to ensure compliance with cleanliness standards.

Regulatory compliance:
Depending on the industry and location, clean rooms may need to comply with various regulatory requirements and standards, which can add to the overall cost through additional documentation, testing, and validation processes.

Allowable concentration of particles per m3?

In ISO Class 1 clean rooms, the allowable concentration of airborne particles per cubic meter of air is extremely low, as this class represents the highest level of cleanliness. The specific particle count limits are defined in ISO 14644-1, which provides standards for clean room classification and testing.

For particles 0.1 micrometers and larger, ISO 14644-1 typically sets the maximum allowable particle concentration in ISO Class 1 clean rooms at:

  • 10 particles per cubic meter of air or fewer for particles of size 0.1 micrometers (µm) – 100 nanometers
  • No specific limit for particles larger than 0.1 µm, as long as the overall particle count remains within the specified limit for 0.1 µm particles

ISO Class 1 clean rooms are used in industries where the highest levels of cleanliness are required, such as semiconductor manufacturing, nanotechnology research, and certain pharmaceutical manufacturing processes. Achieving and maintaining this level of cleanliness requires stringent control measures and regular monitoring to ensure compliance with ISO standards.

The proof of the pudding is in the eating

While the initial investment in building and equipping a clean room can be substantial, the cost is justified by the critical need for cleanliness where product quality is essential. A higher degree of cleanliness requires a higher degree of air purification.

If you could achieve maximum cleanliness – i.e. far above ISO standard 1 – with the same Capex and a lower Opex, what would you decide?

The answer should be simple. A higher level of air filtration will lead to a cleaner ‘workspace’. This will result into a cleaner product and therefor into better results. There is no logical reason not to take advantage of this technical opportunities to implement a 1 nano level air filtering installation of Van Wees Innovations.

I am willing to understand that my proposition is beyond all expectations, but I will be happy to work on a pilot. The proof of the pudding is in the eating. Shall we start with an initial introduction and demonstration of our technology?

Please contact me via +31 6 200 17 111 or email me via

Thank you for your time

Remo Natali
We serve pure air