Cleanroom clothing
Cleanroom clothing and the correct washing cycle are important links in the dust classification of an operational space. Clothing is essentially the packaging of a highly polluting substance – humans – the vulnerable link in a super-clean environment.
The human skin naturally produces millions of flakes, which are released spontaneously with every movement. The higher the classification of the cleanroom, the more important the clothing and packaging are.
Contamination and cleanroom class
Modern manufacturing techniques increasingly require a contamination-free environment; ‘cleanroom’ is the general term for these contamination-free spaces. They are used in various industries, ranging from the manufacture of microelectronics or pharmaceuticals to biotechnology or the food industry. The workwear in these areas is distinctive and is collectively referred to as clean room clothing – sometimes the terms cleanroom suit or cleanroom gowning are also used – but the requirements for this clothing can vary considerably depending on the classification. See the information at the bottom of this page.
Particles and contaminated dust particles
A distinction must be made between cleanrooms for the manufacture of microelectronics, precision components and semiconductors on the one hand and cleanrooms for biotechnology, pharmaceuticals and medical devices on the other.
In the first category of cleanrooms, contamination of components manufactured therein should be avoided, while in the second category of cleanrooms, special conditions are necessary to prevent so-called cross-contamination.
In industrial cleanrooms, floating particles are of paramount importance, while in operating rooms, the importance lies not so much in the number of particles present, but rather in whether these particles are ‘contaminated’ with bacteria.
Clothing
Every person produces a significant number of particles per minute; they ’emit’ or ‘release’ them into the environment. The special clean room clothing used in those spaces is intended to prevent substances originating from the human body from ‘contaminating’ the cleanroom environment. Since a cleanroom suit also constitutes a ‘foreign’ object entering the cleanroom, it is important that this clothing does not release particles or fibers into the environment or cause any additional issues related to the activities or components within the cleanroom.
Requirements
Ensuring the lowest possible emission of particles, as mentioned above and preventing the so-called linting problem involving fiber fragments coming loose from the cleanroom gowning are no longer the only requirements that cleanroom suits must meet. Design, comfort, sterilization, durability and anti-static behavior are additional properties required of cleanroom clothing. The most common type of cleanroom clothing is made from a tightly woven cloth of polyester filament yarns or microfilaments, which is cleaned in a special laundry after weaving. Certain knitted textiles made from the same types of yarn mentioned are also suitable for the production of cleanroom clothing when subject to less stringent requirements.
Assessment standard
It is recommended that to prevent fraying of fabric edges, these (air-laser-cut) edges should be encapsulated within the seams to prevent further particle release. The sewing threads to be used must also be chosen with due care and preferably consist of synthetic filament threads. Preferably, clothing should not have any pockets to prevent dust from accumulating in them.