ISO Cleanroom Classification Guide

Cleanroom classification defines the cleanliness of room air by the concentration of airborne particles. ISO 14644-1 is the international reference commonly used for this classification. The required class should be confirmed together with the operating state, process risk and project acceptance criteria.

What ISO Cleanroom Classification Means

A cleanroom class is a room-performance requirement, not simply a filter grade. Filtration, airflow pattern, air-change strategy, room pressure, leakage control, personnel flow, process load and operating procedures all affect the final measured condition.

ISO Class 5 and Legacy Class 100 Terminology

Many buyers still use the legacy term “Class 100” in drawings and replacement enquiries. In modern project communication it is clearer to state ISO Class 5 (Class 100) and then confirm the applicable project standard, particle-size criteria, room state and validation method before design or acceptance.

Key Factors in Cleanroom Configuration

• Target cleanliness class and operating state
• Room size, ceiling height and production heat load
• HEPA or ULPA terminal filtration requirement
• FFU or ducted airflow distribution method
• Room pressure relationships and contamination-control zoning
• Personnel and material entry routes
• Temperature, humidity and process-specific environmental requirements
• Commissioning, testing and project acceptance requirements

Typical Cleanroom Equipment

Depending on the project, a cleanroom may combine HEPA/ULPA filters, FFU fan filter units, high-efficiency air supply outlets, air showers, pass boxes, clean benches and modular room components. Final equipment selection follows the confirmed room layout and contamination-control requirement.

Selection Checklist

For an initial proposal, provide the application, room dimensions, target cleanliness class, number of operators, equipment heat load, process layout, temperature/humidity requirement and any customer validation standard. BAIHANGDA can then organize a project-specific equipment configuration.

FAQ

Does a higher filter grade automatically create a higher cleanroom class?

No. Filter selection is only one part of the system. The cleanroom must perform as a complete controlled environment and should be tested against the agreed project requirement.

Can an existing room be upgraded?

In many cases, airflow, filtration, zoning or equipment can be upgraded, but feasibility depends on the existing structure, HVAC capacity, process layout and required final performance.