Ventilation technology in clean rooms

A cleanroom is an area in which the air quality is strictly controlled to prevent contamination by dust, particles and microorganisms. The air concentration of these contaminants is kept at a defined level that is required for the respective application. Cleanrooms are used in many industries, e.g. the pharmaceutical industry, medical technology, the semiconductor industry and the food industry.

There are different types of cleanrooms, which can be categorised according to different classifications. A common categorisation distinguishes between ISO classes:

• ISO 1 to ISO 5: These cleanrooms require the highest air purity and are used, for example, in the semiconductor industry and pharmaceutical production.
• ISO 6 to ISO 9: These cleanrooms have less stringent air purity requirements and are used, for example, in medical technology and the food industry.
• ISO classes 8 and 9: These cleanrooms require the lowest air purity and are used in assembly and production, for example.

A ventilation system in cleanrooms consists of various components that work together to control the air quality. The most important components include

• Air intake: The air is drawn in from the environment and pre-filtered to remove coarse impurities.
• Filtration: The air is passed through various filter stages to remove dust, particles and microorganisms.
• Ventilatoren: Fans ensure an air flow through the cleanroom and transport the cleaned air to the air outlets.
• Air outlets: The cleaned air is distributed evenly in the cleanroom via air outlets.
• Climate control: The temperature and humidity in the cleanroom are regulated to create optimum conditions for the respective application.
• Control system: The entire ventilation system is monitored and regulated by a control system to keep the air quality constant.

Filter technology plays a decisive role in air purity in cleanrooms. There are different types of filters that can separate different contaminants. The most common filters include

• Suspended particle filter: These filters remove dust and particles from the air.
• HEPA filter (High Efficiency Particulate Air): HEPA filters remove particles with a size of 0.3 micrometres and larger with an efficiency of 99.97 %.
• ULPA filter (Ultra Low Penetration Air): ULPA filters remove particles with a size of 0.1 micrometres and larger with an efficiency of 99.999 %.
• Gas filter: Gas filters remove gases and vapours from the air.