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Understanding the Distinction: ISO Class 100 vs. ISO 5 Cleanrooms

In the world of manufacturing, pharmaceuticals, biotechnology, and electronics, the concept of cleanrooms is of utmost importance. These specialized environments maintain exceptionally low levels of airborne particles and contaminants to ensure the quality and integrity of sensitive processes and products. Among the various classifications, ISO Class 100 and ISO 5 cleanrooms stand out as benchmarks for cleanliness. But what exactly sets them apart?

Cleanroom in use by medical professionals


Introduction to Cleanrooms

Before diving into the comparison, let's first understand what cleanrooms are and why they are crucial in certain industries.


Cleanrooms are controlled environments where the concentration of airborne particles is meticulously regulated to specific levels. These particles can include dust, microbes, aerosol particles, and chemical vapors, all of which have the potential to contaminate products or processes sensitive to such impurities. Cleanroom contractors and cleanroom consultants play a vital role in designing, constructing, and maintaining these critical environments in accordance with ISO cleanroom standards and classifications.


ISO Class 100 Cleanrooms

ISO Class 100 cleanrooms are among the cleanest environments, adhering to stringent standards set forth by the International Organization for Standardization (ISO). In an ISO Class 100 cleanroom, the concentration of airborne particles larger than 0.5 micrometers per cubic foot of air must not exceed 100 particles. This level of cleanliness is essential for industries where even minute contaminants can compromise product quality or affect research outcomes.

Cleanroom being used for production of microchips


ISO 5 Cleanrooms

ISO 5 cleanrooms, on the other hand, represent an even higher standard of cleanliness. Also known as Class 100 cleanrooms in the Federal Standard 209E classification system, ISO 5 cleanrooms permit a maximum of 3,520 particles of 0.5 micrometers or larger per cubic meter of air. The stricter particle count in ISO 5 cleanrooms makes them ideal for industries where absolute cleanliness is non-negotiable, such as semiconductor manufacturing, nanotechnology, and medical device production.


Key Differences

Particle Count: The primary distinction between ISO Class 100 and ISO 5 cleanrooms lies in the allowable particle count. ISO 5 cleanrooms maintain a significantly lower particle concentration compared to ISO Class 100 cleanrooms, making them suitable for applications demanding the utmost cleanliness.


Applications: While both types of cleanrooms are used in industries with strict cleanliness requirements, ISO 5 cleanrooms are typically reserved for processes and applications where even minimal contamination can have severe consequences. Industries such as semiconductor manufacturing, biotechnology, and aerospace often require ISO 5 cleanrooms for their critical operations.

Maintaing a sterile cleanroom

Stringency of Standards: ISO 5 cleanrooms adhere to more stringent standards compared to ISO Class 100 cleanrooms. The heightened level of cleanliness in ISO 5 cleanrooms necessitates stricter control measures and maintenance protocols to uphold the desired cleanliness levels consistently.


To sum things up, both ISO Class 100 and ISO 5 cleanrooms play crucial roles in industries where contamination control is paramount. While ISO Class 100 cleanrooms offer a high level of cleanliness suitable for many applications, ISO 5 cleanrooms represent the pinnacle of cleanliness standards, making them indispensable for industries that demand absolute precision and purity. Cleanroom contractors and cleanroom consultants are instrumental in ensuring the design, construction, and maintenance of these cleanroom facilities in accordance with appropriate cleanroom classifications and ISO standards. Understanding the differences between these cleanroom classifications is essential for selecting the appropriate environment to ensure product quality, process integrity, and compliance with industry regulations.


For inquiries regarding cleanroom consulting services or to discuss your specific cleanroom project requirements, please don't hesitate to contact us. At DesignTek Consulting, our team of experts is dedicated to providing comprehensive cleanroom solutions tailored to your industry needs. Whether you're seeking assistance with cleanroom design, construction, certification, or maintenance, we're here to help. Contact us today to schedule a consultation and take the first step toward achieving optimal cleanliness and compliance with ISO cleanroom standards.

CONTACT US AT (855) 203-2958


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