How are cleanroom classifications determined and why do they matter in CBM T6?

• A. ISO 14644 particle classifications; classification dictates gowning, cleaning, testing, and controls.
• B. Room color determines classification.
• C. Flooring type determines classification.
• D. Cleanliness determined by staff mood.

Answer: (A)

The key idea is that a cleanroom’s classification comes from ISO 14644-1 particle-count criteria, not appearance or room features. Cleanroom classes are defined by how many particles of specified sizes are allowed per cubic meter, which sets the maximum concentration the space can tolerate during operations. Because that limit defines how clean the environment must be, it directly drives the required controls: how personnel must dress (gowning), how often and how thoroughly the room must be cleaned, what tests are performed to verify cleanliness, and how the room is monitored and controlled (airflow, filtration, pressure differentials, and routine certification). In CBM T6, this matters because staying within the designated class minimizes contamination risk to processes and products, ensuring quality and providing an auditable basis for maintenance, validation, and regulatory compliance. Choices based on color, flooring, or staff mood don’t reflect an objective cleanliness standard and therefore don’t determine classification.