Types of Cleanrooms
Cleanroom facilities incorporate a variety of preventative materials, equipment and devices to maintain a highly clean, germ-and-bacteria-free environment. Some of this equipment is for extensive personnel protection, while other pieces are designed to maintain clean air in the workplace. Cleanrooms are typically used for manufacturing and scientific research operations that require processes or materials that are incredibly sensitive to dust, static electricity, or various types of microparticles and microorganisms. For instance, computer parts often have small parts that cannot be contaminated by dust before they are assembled into a final housing.
Cleanrooms are used for production and research and commonly featured elements such as HEPA (highly-efficient particulate air) filters, air showers, special garments for workers to wear, and anti-static devices in order to limit contamination or damage to the workplace environment. Because of the varied nature of cleanroom work, cleanroom facilities are available in portable and modular designs as well as fixed building structures.
Types of Cleanrooms
Cleanrooms are often needed for emergency work and short run production jobs. For emergency work, there are modular, temporary cleanroom structures that can be constructed in a short period of time and disassembled when the job is over. These types of portable cleanrooms can be assembled outdoors and in existing facilities, such as warehouses. Many portable and temporary cleanrooms are constructed as “softwall” cleanrooms, meaning their walls are constructed from transparent polymers. Typically, softwall and other types of modular cleanrooms can be fitted with portable or small-scale HEPA filters, anti-static devices and garment change facilities just like permanent cleanrooms, and can maintain similar levels of cleanroom sterility.
Cleanrooms are graded according to cleanliness standards maintained by the International Organization for Standardization (ISO). These quantified grades represent the number of particles 0.1 micrometers or larger permitted per cubic meter of air. The number is further standardized by having the ISO grade correspond to a logarithm for determining particle count. For example, ISO 3 cleanrooms feature a maximum of 103 particles per meter cubed, or 1000 particles.
The United States Department of Commerce officially maintained a cleanroom standard, US FED STD 209E, until 2001. Despite its official abandonment, this standard is still commonly used by North American manufacturers.
Depending on the official grade of the cleanroom and the types of materials manufactured or used in the facility, there are a wide variety of accessories available for cleanroom use and labor. For instance, some computer parts can easily be damaged by static build up, so anti-static garments, floor mats and bracelet/anklet devices exist for static prevention. Additionally, cleaning devices that target specific items, like worker shoes, can be installed in a facility. Most types of standard pieces of laboratory equipment are available in “clean” versions, which are equipment pieces that have been modified or enhanced specifically for a cleanroom environment.