What is Cleanroom

A clean room is a room where the concentration of particles is minimized. Temperature, humidity and pressure parameters are also controlled.

Operators use particular clothes (foot booties, coat, hairnet and gloves) to avoid dirtying the room.

Clean rooms are used for the industry or research fields, which are sensible domains to environmental contamination (biology, construction of spacecraft, optical manufacturing or semiconductors…).

To cope with rising demands of optics and space applications, an ISO 7 (class 10 000) clean room has been installed to minimize the presence of particles such as dust to enable the integration of “clean” and vacuum compatible hexapods.

In the space sector, we regularly deliver ISO 5 compatible systems, for which we follow the design and assembly rules related to the cleanliness of the ISO 5 environment.

A cleanroom or clean room is an engineered space, which maintains a very low concentration of airborne particulates. It is well isolated, well-controlled from contamination, and actively cleansed. Such rooms are commonly needed for scientific research, and in industrial production for all nanoscale processes, such as semiconductors & medicine manufacturing. A cleanroom is designed to keep everything from dust to airborne or vaporized particles, away from it, and so from whatever material is being handled inside it.

Cleanrooms typically come with a cleanliness level quantified by the number of particles per cubic meter at a predetermined molecule measure. The ambient outdoor air in a typical urban area contains 35,000,000 particles for each cubic meter in the size range 0.5 μm and bigger, equivalent to an ISO 9 certified cleanroom. By comparison an ISO 14644-1 level 1 certified cleanroom permits no particles in that size range, and just 12 particles for each cubic meter of 0.3 μm and smaller. Semiconductor facilities often get by with level 7, while level 1 facilities are exceedingly rare.

Some cleanrooms are kept at a positive pressure so if any leaks occur, air leaks out of the chamber instead of unfiltered air coming in. This is most typically the case in semiconductor manufacturing, where even minute amounts of particulates leaking in could contaminate the whole process, while anything leaking out would not be harmful to the surrounding community. The opposite is done e.g. in the case of high level bio-laboratories, handling contaminous viruses; those are always held at negative pressure, with the exhaust being passed through high efficiency filters, and further sterilizing procedures. Both are still cleanrooms, because the particulate level inside is maintained within very low limits.

Some cleanroom HVAC systems control the humidity to such low levels that extra equipment like air ionizers are required to prevent electrostatic discharge problems. This is a particular concern within the semiconductor business, because static discharge can easily damage modern circuit designs. On the other hand, active ions in the air can harm exposed components as well. Because of this most workers in high electronics and semiconductor facilities have to wear conductive boots while working. Low-level cleanrooms may only require special shoes, with completely smooth soles that do not track in dust or dirt. However, for safety reasons, shoe soles must not create slipping hazards. Access to a cleanroom is usually restricted to those wearing a cleanroom suit, including the necessary machinery.

In cleanrooms in which the standards of air contamination are less rigorous, the entrance to the cleanroom may not have an air shower. An anteroom (known as a “gray room”) is used to put on clean-room clothing. This practice is common e.g. in many nuclear power plants, which operate as low-grade inverse pressure cleanrooms, as a whole.