ISO 14644-1 Class 8 Cleanrooms – Class 100,000 Cleanroom Requirements

Whenever sterility and cleanliness are required, cleanrooms are used. The HEPA filter in a cleanroom removes particles from the air to help it remain clean. These rooms are used for manufacturing medical devices, pharmaceuticals, and semiconductors. In GMP factories, cleanrooms are necessary for manufacturing, requiring a high level of cleanliness and sterility. Moreover, there are electronic cleanrooms, biotech cleanrooms, food cleanrooms, USP797 compounding pharmacy cleanrooms, and aerospace cleanrooms. The government and defense industries, universities, and national labs also use cleanrooms.

In these rooms, the air is cleaned not only with HEPA filters but also with ULPA filters and, when needed, with dehumidifiers. In addition, an ideal temperature for any cleanroom is 21 degrees Celsius (69.8 degrees Fahrenheit). Normally, a fluctuation of 2 degrees Celsius is acceptable.

Speaking about standards, the ISO is an international organization that sets standards. ISO 4644-1 Cleanroom Standards define the maximum particle size, the maximum particle number, and the number of HEPA filtered airflow changes per hour that meet ISO-4, ISO-5, ISO-6, ISO-7, and ISO-8 standards. Measurements are made per cubic meter. Fed Standard 209E, a standard based on measurements per cubic foot, is the equivalent in the US. As per Federal Standard 209E, there are classes 10, 100, 1000, 10000, and 100000.

ISO 14644-1 Class 8 Cleanroom Standards and Classifications

An ISO 8 cleanroom, also known as a Class 100,000 cleanroom, has a particle count of 100,000 particles (0.5 um) per cubic foot and is modular or soft-walled. For your project needs, they offer significant particle protection. The maximum particle concentrations per room are limited and require frequent air changes. For applications requiring moderate particle concentration limits within a given area, ISO 8 cleanrooms are recommended. HEPA filtration is needed to cover over 5% of the area and provide at least 20 air changes per hour with airflow rates of 4-8 CFM per square foot. Certain particle sizes aren’t tested in ISO 8 clean rooms either because the concentration levels are too high or too low, but they can’t be zero. ISO Class 8 excludes particles smaller than 0.5 m as their concentration should be smaller than 3,520,000.

ACH (air change per hour) is crucial in cleanroom design. Occasionally, filtered air in a cleanroom is replaced by existing air. Depending on its usage and classification, it occurs between 10 and 600 times an hour. There are between five and 48 ACRs in ISO Class 8 cleanrooms.

Also, an ISO cleanroom can be entered directly from any unclassified space (office or lab) if the space is ISO 9. However, depending on the manufacturing process inside the cleanroom, you might need a gowning room.

• Modular cleanrooms are fully enclosed with hard walls mounted between anodized aluminum posts. In comparison to soft wall cleanrooms, rigid walls allow for increased internal air pressure levels, which minimizes the possibility of dirty air entering the room.
• Softwall Cleanrooms: These cleanrooms are typically smaller and more functional while delivering all the advantages of modular construction. Tent-like softwall cleanrooms are lightweight and simple to assemble. Depending on your needs, they may be installed as freestanding structures or hung from the ceiling.

For testing and characterizing ISO 8 cleanroom performance, 3 levels of conditions are defined:

• At Built: It refers to an empty cleanroom and filtration runs. Nobody is present in the cleanroom. Despite never being used, the cleanroom is in the best possible condition.
• At Rest: Once products and equipment are added to a cleanroom, it is said to be ‘at rest’. However, no tests have been conducted in the room. Compared to the ‘at built’ state, the room may only rate ISO 6.
• In Operation: The cleanroom becomes operational once tested for performance requirements, benchmarked, and documented. Cleanrooms are now used for their purpose, with people and equipment within. This is the dirtiest time for a cleanroom because people and processes contaminate it. Contaminants in the operational state will be corrected if they do not comply with ISO Class 8 requirements.

Design and Requirements for Class 100,000 ISO 8 Cleanroom

Depending on the industry and application, a cleanroom design must consider additional regulatory standards. For an ISO 8 cleanroom, several general requirements and environmental criteria need to be addressed. They are listed below:

As ISO 8 cleanrooms are designed to measure particles 0.5 microns or larger, the HEPA filtration system should be 99.97% efficient, and at least 20 air changes per hour should be performed. Upon entering the cleanroom, the air is filtered once more. Moreover, ISO 8 cleanrooms are mostly designed with non-unidirectional and mixed airflow patterns and low wall air returns.

Control the Contaminant Levels in an ISO 8 Cleanroom

Keep the contaminant level low in a cleanroom can be demanding, but here are a few habits everyone can acquire:

• Mop floors with a damp mop and vacuum to dry them before your shift begins.
• Make sure all products and supplies are stored between shifts.
• Always wear the proper protective equipment.
• Remove debris from all windows and doors.
• Use a HEPA vacuum to clean all walls.
• Provide exclusive cleanroom supplies.
• Constantly keep your hands clean.
• Limit your speaking.

ISO 7 vs. ISO 8: What’s the Difference?

As we have already mentioned, cleanrooms are spaces that are kept exceptionally sterile or free of dust and particles to ensure they are safe for anything that needs to be cleaned. ISO Class 1 is the cleanest, and ISO Class 9 is the dirtiest. To qualify for classification, a room must meet multiple criteria.

Basically, you can use ISO7 and ISO 8 in the same industries, but they differ in the number of air changes per hour.

Thus, the most important differences between ISO 7 and ISO 8 cleanrooms are particle count and ACH requirements, making them suitable for different applications. ISO 7 cleanrooms require 352,000 particles and 0.5 microns per cubic meter, while ISO 8 cleanrooms require 3,520,000 particles and 20 ACH.