A Clean Design
The way in which a cleanroom is designed depends on several factors, including the classification, which ordains the amount of particles or microbes that are allowable in one cubic foot of air. Also, the specific application of the cleanroom will determine much of the design as some products are more susceptible to contamination or to certain kinds of contamination than others. Though the class level and application cause specific variants among these work stations, most cleanroom designs employ similar means of controlling airflow and minimizing traffic as these are crucial factors in all cases.
The floor plan as far as the layout of the equipment is crucial in terms of minimizing traffic. Unnecessary movement and traffic disrupts airflow and, even with protective garments, can cause the release of more particles into the air from the person. As far as airflow, there are two options for ventilation: laminar air flow and turbulent air flow. Laminar flow is used most often in cleanrooms, as it supports continual air processing by means of a unidirectional flow. Several conditioners in the ceiling force the air downward to filters in the wall or, often times, through a grated floor to be recirculated. Turbulent systems also keep air in constant motion, but in several directions in order to trap particles and move them toward filters or into the grates.
Flooring is also a major component of cleanroom design. As I mentioned, grated floors are ideal for optimum air flow. Unfortunately, these gratings can be particularly uncomfortable to stand on for long periods of time. This has lead to alterations in the layout (installing floor grating in selective places where workers do not stand as often) as well as modifications in grating systems themselves. There is a continual evolution in construction concepts to improve working conditions as well as sterility, and it all comes down to a clean design.