In the last three decades there has been an increasing emphasis on the importance of the use of fidelity assessment on improving the science of psychological, social, and behavioral research.
A cleanroom is an area or enclosure in which the air has to be cleaned to a defined particle limit, usually in particles per cubic foot. In the United States most cleanrooms are discussed in terms of Classification Limits.
Cleanroom and clean air equipment standards have for many years defined classes of cleanliness and how they are to be assessed. However there has never been any requirement to test a cleanroom at any point in its often very long lifetime, other than at the time of handover from supplier to purchaser.