Cleanroom Basics

It is often only a small step from a controlled room to a qualified cleanroom of ISO 8 standard according to EN ISO 14644-1. This depends on existing influences from the surroundings on site or from neighbouring production or storage facilities and also on the materials used and on the clothing of cleanroom-trained staff.

A cleanroom or ultra clean room is a room where the number of airborne particles or particulates is kept as low as possible. In order to create and maintain the desired cleanroom atmosphere, a closed room of pressure-tight construction is required, allowing for constant temperature, humidity levels and pressure conditions.

As people usually present the biggest contamination risk, personnel airlocks are essential. The clothing of the staff working in the cleanroom is also fundamental and must be chosen with cleanroom class, activity and product in mind.

In-and-out traffic of materials must be controlled with suitable airlock or hatch systems in order to ensure process-safe operation of the cleanroom (interlocking doors etc.).

Normally, several cleanrooms of different classes are combined and often entered through multi-level [different] airlocks. Here too, the correct concept for one-way or reusable clothing and for consumables plays an important role.

Excessive room pressure, air exchange rate and flow speed [turbulent, laminar] depend on the required cleanroom class. In rooms of different classifications, there will be different room pressures [pressure cascades]. Their control relationship [e.g. room 2 – room 1 – airlock] can be implemented using differentiated control and regulation modules.

Continuing testing and documentation of the cleanroom class desired or implemented can take place with portable particle measuring devices or by installing a permanent monitoring system.