When we talk about pharmaceutical production, precision manufacturing or cutting-edge research, one critical element often works behind the scenes: the cleanroom. You can think of it as a carefully tuned environment where microscopic particles are controlled to protect sensitive processes from contamination. But how do we define cleanroom cleanliness? That is where cleanroom classifications come in, and they give us measurable benchmarks to design, validate, and operate.
As your fully experienced cleanroom partner, KINROM navigates these standards daily. In this article, we will present to you three of the most common standards: US FED STD 209E, ISO 14644-1, and European GMP Annex 1. We will share how each one emerged, how they relate to one another and their applications.
Cleanroom Classifications - US FED STD 209E
The concept of classifying cleanrooms by “cleanliness level” was first widely established by the U.S. Federal Standard 209E. It introduced the now-familiar classes—Class 1, Class 10, Class 100, up to Class 100,000—based on the maximum allowable number of particles per cubic foot of air.
However, this standard was officially withdrawn in November 2001 and replaced by the international ISO 14644. While no longer active, US FED STD 209E remains important for understanding historical documents and some legacy systems. In the table below, we break down its original classification levels for reference.
Cleanroom Classifications - ISO 14644-1
Currently, the globally recognized benchmark for cleanroom classification is ISO 14644-1. It has shifted the unit of measurement from cubic feet to cubic meters and defines cleanroom classes from ISO 1 to ISO 9, based on permitted concentrations of airborne particles.
Cleanroom Classifications - European GMP Annex 1
In pharmaceutical and biotechnology manufacturing, cleanrooms are governed by Good Manufacturing Practice (GMP) guidelines, such as the EU GMP Annex 1. The table below outlines the typical GMP grades (A, B, C, D), their equivalent ISO classifications, and their associated applications in sterile production.
Is a Higher Cleanroom Class Always Better?
The selection of a cleanroom class is not a matter of “the higher, the better.” Instead, it requires a precise match with the actual needs of the production process. Over-specifying the cleanliness level often leads to significant waste in both capital investment and operational expenses.
We take glass processing as an example, general glass processing may only require ISO Class 8, while optical lens coating or semiconductor lithography might need ISO Class 5 or higher. If a general glass processing factory owner blindly pursuing cleanroom cleanliness level from ISO 8 to ISO 5, a substantial rise in HEPA filter coverage, fan power, and air change rates is required, which leads to making more electricity costs and a long-term burden.
Contact Us for More Information of Cleanroom Classifications
KINROM is a professional cleanroom solution begins with a deep understanding of the process and a holistic consideration of costs. We not only build cleanrooms but also provides integrated consulting and design that balances compliance, reliability, and economy from the initial planning stage.
If you are planning a cleanroom project or seeking to optimize the energy efficiency of an existing facility, feel free to contact the KINROM team for a professional preliminary assessment and a tailored solution.
