Cleanroom classifications are most commonly based on the number of particles of a certain size in a cubic meter of air, but they can also be classified according to air cleanliness by chemical concentration and surface cleanliness by particle or chemical concentration.
The International Standards Organization governs all cleanroom classifications under ISO 14644. ISO 14644 covers more than just cleanroom classifications though. It also addresses monitoring and proving air cleanliness, how to test to determine the cleanliness classification, cleanroom design and construction, cleanroom operations, and separative devices.
Air Cleanliness by Particle Concentration
For cleanrooms that are classified by the number of particles of a certain size in a cubic meter of air, there are nine total classifications: ISO 1 through ISO 9. The definitions for each classification range from having a maximum of 10 particles that are greater than or equal to 0.1 micrometers per cubic meter to a maximum of 293,000 particles that are greater than or equal to 5 micrometers per cubic meter.
For each of these cleanroom classifications, certain criteria must be met. These include air changes per hour or minute, filter coverage percentage, cubic feet per minute per square foot, filter efficiency, ceiling type, light fixture type, ceiling panel, wall system, flooring cover, flooring base, and air returns. For example, for ISO 4, the filter coverage needs to be 90-100 percent, but for ISO 8, the filter coverage only needs to be 4-5 percent.
How Cleanroom Classifications Affect Cleaning and Inspections
In addition to defining the criteria that must be met, the cleanroom classification determines how the cleanroom must be cleaned and what requirements need to be met for inspections and quality checks. It’s extremely important that the party in charge of ensuring that your cleanroom meets regulations is familiar with your cleanroom’s classification and the impact which that classification has on the cleanroom’s cleanliness.
Cleanroom training, at a minimum, should cover ISO 14644 definitions in addition to Food and Drug Administration (FDA) and Good Manufacturing Practice (GMP) requirements, cleanroom terminology, general protocol, entry and exit procedures, equipment and supply usage and care, contamination control, personal hygiene, standard operating procedures, basic microbiology, particle and sterile cleaning, static control, and documentation.
Without thorough understanding of the above principals, the most basic and important of which is cleanroom classification, you run the risk of contaminating products, which can have negative effects on both your business and your end users.
Ensure Your Compliance with Regulations
Once you know how your cleanroom is classified, you can begin to determine what requirements need to be met to ensure your compliance with regulations. However, classification itself is tricky, not to mention all the tasks involved in meeting requirements. If you manufacture products in a controlled environment, it’s in your best interest to hire a third-party organization that is wholly focused on proper cleaning procedures for controlled environments.
Standard janitorial or housekeeping staff is not properly trained on cleanroom classifications and requirements. Don’t put your company or your customers at risk. Go the extra mile by employing the services of a company that truly understands the cleanroom cleaning process and all its nuances to ensure you are operating in the most effective, efficient, and ethical manner at all times.