Common Cleanroom Engineering Classifications
Classification by cleanliness level is the most core and fundamental method of cleanroom engineering. The standard is primarily based on the international standard ISO 14644-1, with the core evaluation indicator being the concentration of suspended particles ≥0.5μm in the room. Based on concentration differences, cleanliness levels are divided into ISO 1 to ISO 9, each corresponding to different application scenarios: ISO 1 to ISO 5 represent high cleanliness levels, often referred to as Class 100 or Class 10 cleanrooms, with extremely high requirements for particle control. They are mainly used in fields with stringent environmental purity requirements, such as chip manufacturing, high-end pharmaceutical aseptic production, and tertiary hospital operating rooms; ISO 6 to ISO 7 represent medium cleanliness levels, corresponding to Class 1000 and Class 10,000 cleanrooms, balancing cleanliness and cost, and are widely used in industries such as electronic component assembly, medical device manufacturing, and food packaging; ISO 8 to ISO 9 represent ordinary cleanliness levels, namely Class 100,000 and Class 300,000 cleanrooms, with relatively relaxed cleanliness requirements, and are mostly used in ordinary food processing, cosmetics production, and ordinary packaging workshops.
Airflow organization is a key factor determining the cleanliness of a cleanroom. Based on this, cleanrooms can be categorized into three types: unidirectional flow, non-unidirectional flow, and mixed flow. Unidirectional flow cleanrooms, also known as laminar flow cleanrooms, use unidirectional airflow (vertical or horizontal) to evenly cover the entire indoor space, effectively removing indoor contaminants. Cleanliness levels can reach Class 100 and above, making them suitable for scenarios with extremely high cleanliness requirements. Non-unidirectional flow cleanrooms, also known as turbulent flow cleanrooms, use a mixed and diluted airflow method, with no fixed airflow direction. They are relatively low-cost and are often used in cleanrooms with medium to low cleanliness levels, such as Class 10,000 and Class 100,000. Mixed flow cleanrooms combine the advantages of the former two, using a combination of localized unidirectional flow and overall non-unidirectional flow. This ensures high cleanliness in the core area while controlling overall project costs, and is currently the most widely used airflow type in the industry.
Classification by application is the most practical way to categorize cleanrooms. Based on the needs of different industries, cleanrooms can be divided into four main categories: industrial cleanrooms, biological cleanrooms, operating room cleanrooms, and food/cosmetic cleanrooms. Industrial cleanrooms primarily serve industries such as electronics, semiconductors, precision manufacturing, and optical instruments. Their core requirement is controlling dust and static electricity to prevent contamination of precision products. Biological cleanrooms focus on pharmaceuticals, biological laboratories, GMP workshops, and P2/P3 laboratories, prioritizing the control of microorganisms and bacteria to ensure product and experimental safety. Operating room cleanrooms are mainly used in hospitals, categorized into Class I, II, and III based on surgical complexity, reducing the risk of surgical infection by controlling indoor microorganisms and dust. Food/cosmetic cleanrooms are built according to QS and GMP standards, controlling dust and microorganisms during production to ensure the hygiene and safety of food and cosmetics.
Based on the controlled objects, cleanrooms can be classified into airborne particle control cleanrooms, microbial control cleanrooms, anti-static cleanrooms, and anti-vibration cleanrooms. Particle control cleanrooms primarily control indoor dust and suspended particulate matter, and are the core type of cleanrooms in industries such as electronics and optics. Microbial control cleanrooms focus on controlling bacteria, fungi, and other microorganisms, suitable for fields with extremely high hygiene requirements such as pharmaceuticals, medical devices, and food processing. Anti-static cleanrooms are mainly for industries such as semiconductors, chips, and precision electronics, controlling indoor static electricity to prevent damage to sensitive components. Anti-vibration cleanrooms are used in scenarios such as precision instrument manufacturing and photolithography equipment operation, controlling indoor vibration amplitude to ensure the accuracy of precision operations.
In the engineering construction field, classification by structural form is also commonly used, mainly divided into three categories: civil engineering, modular, and clean booth. Civil engineering cleanrooms are the traditional construction method, completed through on-site pouring and finishing. They offer structural stability and good sealing, but have long construction cycles and high costs, making them suitable for large, fixed cleanroom locations. Modular cleanrooms utilize prefabricated construction, with components prefabricated and assembled on-site. They offer fast construction speed, relocation capability, and high flexibility, making them a preferred choice for many companies, especially suitable for scenarios requiring frequent layout adjustments. Clean booths are a type of simple cleanroom, primarily used for localized purification. They are simple in structure, low in cost, and can be quickly erected, suitable for temporary cleanroom needs or localized purification upgrades.
In summary, the various classifications of cleanroom engineering are not independent but rather combined based on actual application requirements. For example, GMP workshops in the pharmaceutical industry are both biological cleanrooms and require a cleanliness level of approximately ISO 5, while also employing unidirectional or mixed airflow. Understanding the common cleanroom classifications helps in selecting the most suitable cleanroom solution based on industry needs and budget, ensuring the clean environment meets standards while also being practical and economical.