What’s a Clean Room?
A clean room is an enclosed space employing environmental control over atmospheric contamination, temperature, humidity, and pressure. The cleanliness of the space is defined by ISO Standard 14644-1, which replaced Federal Standard 209E.
This standard (ISO 14644-1) is a document defining the number and size of the particles in a clean room environment. The specification looks at a clean room as a total system. It does not classify the individual components that make up the clean room.
What are the typical Clean Room applications?
Clean rooms are often found in facilities created for the manufacture of microelectronics, optics, pharmaceuticals, and other industries where activities requiring special attention can be as diverse as growing a crystal in a lab to replacing a hip in an orthopedic operating room.
In all cases, the number and size of the particles in the atmosphere must be controlled.
In today’s technologically demanding environment, a little bit of dirt can cause a great deal of trouble.
For instance, a speck of dust so small it can only be seen under a powerful microscope, could throw a spacecraft’s guidance system off sufficiently enough to cause the spacecraft to miss the moon by many miles. Because these microscopic amounts of foreign matter can create such problems, aerospace industries must meet fantastic standards of cleanliness.
These standards can’t be maintained if sensitive electronic components are manufactured in conventional production areas.
How small are particles measured in Clean Room?
Airborne particles, because of their small sizes, are measured in microns (uM).
Clean rooms are typically concerned with particles of 0.5 microns to 100 microns. The cleanliness level is controlled by laminar flow, constantly flowing the air along a parallel path, usually from the ceiling to the floor. The air is cleaned by passing it through high efficiency particulate air (HEPA) filters.
In order to maintain the desired level of cleanliness, the room must be free of materials that will release particles.
A positive pressure is always maintained in the higher class clean room; e.g., a Class 5 clean room will be maintained at a higher pressure than the Class 6 anteroom, which will be at a higher pressure than the outside hallway