Let us compare the numbers of airborne particle or micro organism in cleanroom with our surrounding environment. The numbers of particles in general environment vary from time to time so that any fixed number cannot be determined, but roughly classified as shown in the diagram to the right. From this figure, you will see that such a clean condition in the highest class cleanroom cannot be found in the natural world, even in the upper area of stratosphere. Also, in the center of Pacific Ocean, the cleanliness level of the air is lower than that of middle class of cleanroom. In other words, cleanroom is an ultra clean space where airborne particles or micro organism are been eliminated, as we can never experience in our normal environment.
We will look at several areas of concern to get a better idea of the overall picture of contamination control. These are the things that need to be considered when providing an effective contamination control program.
A cleanroom provides a controlled, isolated environment for handling contamination-sensitive substances or for protecting the exterior environment from dangerous substances in the controlled area. The density of sub-micron and larger airborne particle contamination inside a cleanroom is kept within tightly controlled limits by forcing clean, filtered air into the cleanroom.
A cleanroom or clean room is an environment, typically used in manufacturing or scientific research, with a low level of environmental pollutants such as dust, airborne microbes, aerosol particles, and chemical vapors. More accurately, a cleanroom has a controlled level of contamination that is specified by the number of particles per cubic meter at a specified particle size.
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