If you need an environment that meets strict industry standards for air purity, understanding cleanrooms and their classifications is key.
Maintaining the right level of cleanliness supports product quality, safety and compliance. There are multiple International Organization for Standardization (ISO) classifications and standards, so it’s not always clear what each one means or how to determine which is right for your needs.
Learn about ISO cleanroom classes and requirements.
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ISO cleanroom standards are regulations for controlling air cleanliness and minimizing contamination in a workspace. At the core of these standards is ISO 14644, a globally recognized set of guidelines that classify cleanrooms based on the number of airborne particles allowed per cubic meter of air. The lower the class number, the stricter the cleanliness requirements. For example, a Class 1 cleanroom permits fewer contaminants than a Class 8 cleanroom.
ISO 14644 also guides how cleanrooms should be designed, operated and maintained. Some features of an ISO-certified cleanroom include the following:
Other key aspects of ISO cleanroom requirements are validation and ongoing monitoring. This involves regular particle count testing, airflow velocity measurements and environmental monitoring to comply with the standards. If a cleanroom falls out of spec, organizations must make adjustments to prevent contamination.
ISO Class 1 is the highest standard of cleanroom classification. It’s the most pristine and tightly controlled environment possible. In an ISO Class 1 cleanroom, the number of airborne particles is almost nonexistent because it allows no more than 10 particles per cubic meter.
Class 1 cleanrooms are ideal for semiconductor packaging and assembly and nanotechnology research. Achieving Class 1 cleanliness requires a fully integrated contamination control strategy. This includes:
Class 2 cleanrooms are only slightly less strict than Class 1, yet they still require extraordinary control measures. These cleanrooms allow no more than 100 particles per cubic meter of air. Applications of Class 2 cleanrooms include semiconductor fabrication and electronic part manufacturing.
Many of the requirements for Class 1 apply to Class 2. Rules include:
ISO Class 3 cleanrooms are among the highest level of contamination-controlled environments, allowing only 1,000 particles per cubic meter. While this is a step down from Class 1 and 2, it’s still far cleaner than everyday environments. Common applications include medical device production, pharmaceuticals, biotech and semiconductor manufacturing.
Class 3 cleanrooms require the following:
A Class 4 cleanroom lets only 10,000 particles per cubic meter. This classification is widely used in pharmaceuticals, biotechnology research, optical equipment manufacturing and microelectronics manufacturing. Below are Class 4 cleanroom requirements:
ISO Class 5 cleanrooms permit 100,000 particles per cubic meter. Although they have significant contamination control, they are one of the commonly used cleanroom classifications because they provide more practical workspace operations. Class 5 cleanrooms are widely used in pharmaceutical manufacturing, medical device production and aerospace and defense. ISO Class 5 cleanrooms must meet strict air filtration and contamination control, including:
A Class 6 cleanroom allows up to 1 million particles per cubic meter. This classification serves as a middle ground between ultra-clean environments and more lenient classifications. Class 6 cleanrooms are commonly found in biotechnological research, pharmaceutical manufacturing and optics and lens manufacturing.
An ISO Class 6 cleanroom must adhere to the following standards to maintain compliance:
Class 7 cleanrooms are among the most widely used cleanroom classifications across multiple industries. They allow 1 million particles per cubic meter and are a versatile choice for medical device production, pharmaceuticals and automotive electronics.
Maintaining ISO class 7 cleanroom standards requires:
Like Class 7 cleanrooms, ISO Class 8 cleanroom standards allow 1 million particles per cubic meter, making it one of the least stringent classifications. These cleanrooms do not require strict contamination control measures, but they still need to protect sensitive processes from airborne particles. Class 8 cleanrooms are widely used in food production and industrial manufacturing. ISO Class 8 cleanroom requirements include:
Class 9 is the least stringent cleanroom classification because it allows 352 million particles per cubic meter. Despite its high particle allowance, it follows some level of contamination control to maintain a cleaner-than-average workspace. These cleanrooms may be used for packaging zones and industrial environments. Although the Class is not as strict as the others, workers should keep the following in mind:
The term Class 10 cleanroom comes from the previous Federal State (FS) 209E standard, which categorized cleanrooms based on the number of particles allowed per cubic foot. Under this system, a Class 10 cleanroom meant there were no more than 10 particles per cubic foot of air. In ISO classification, this level of cleanliness is close to ISO Class 4.
A Class 10 cleanroom requires:
At Starrco, we manufacture modular cleanrooms that give you the air purity and compliance you need. Our cleanrooms are installed 50 to 75% faster, so you can get up and running with minimal disruption. We also offer customizable options to meet ISO standards and your project needs.
Request your free quote today to get started.
