Operating a cleanroom both safely and cost-effectively can best be accomplished by combining strong attention to the lessons of the past with knowledge of today's laundry technologies and state-of-the-art fabrics applicable for cleanroom wear.
Uniform service providers that offer reusable cleanroom garment processing provide assistance to customers that goes beyond simply providing apparel, picking up soiled garments, laundering them and delivering clean ones. When these companies consult with clients, they work to make sure that all choices best meet customer needs and requirements specific to the industry and to the production process located in the controlled environment.
The Uniform and Textile Service Association (UTSA) makes these recommendations for management of cleanroom apparel programs:
Be aware that despite many advances in fabric technology, the primary objective of today's cleanroom garments is the traditional goal: To form a particulate barrier to help prevent contaminants carried by workers from entering the controlled environment and making contact with equipment or product. Potential contaminants may be biological or chemical. Human contaminants include bacteria, lint and the millions of skin flakes that the human body sheds daily.
Properly planned and maintained cleanroom garment systems are highly effective at protecting products from human and environmental contamination. Cleanroom apparel alone, however, cannot guarantee that workers will not be exposed to hazardous materials used in production. Depending on the level of risk, options ranging from splash-resistant fabrics to liquid-tight suiting will provide some protection. Compliance with cleanroom gowning protocols and proper handling of materials by workers, however, still is an absolute requirement to ensure that workers are not harmed by skin contact with hazardous substances such as chemicals. No cleanroom garment system is a replacement for effective employee training, highly visible material safety data sheets, safety reminders, gowning order posters, safety audits, etc‥
Cleanroom garments must permit the body to breathe;
Garments must allow the cleanroom worker flexibility to move as needed to perform all required tasks.
The garment system must meet site-specific requirements of the product or process, such as static dissipation at microelectronic production sites, protection from hazardous vapors, etc‥
The garment must not itself contribute to particulate contamination.
Today's Cleanroom Wear
Whether reusable cleanroom garment processing takes place at a garment rental and processing facility, or at a manufacturer's on-premises laundry, ideally the laundry site will have ISO (International Organization for Standardization) certification with validated processes. Garment processing facilities may be ISO-certified at varying class levels to reflect the number of particles of a particular size in a cubic foot of air at any moment. ISO is a private, worldwide organization setting management and environmental standards for regulatory requirements.
Polyester traditionally has been considered the most practical fabric for reusable cleanroom wear because of its non-lint generating filaments. Sterilization during processing and gamma processing in particular will break down any fabric fiber, including polyester, to some extent. Fortunately, manufacturers work continually to improve the expected life of reusable cleanroom garments by improving the technology and yarns used in the weave.
This commitment by manufacturers underscores the importance of assessing your company's cleanroom gowning requirements in comparison with ISO standards, OSHA requirements and any other applicable regulations on a regular basis. Like the fabrics, regulations also change. Thus, even if your production processes are stable for long periods of time, it is worthwhile to re-examine cleanroom garment systems and protocols often to ensure that they are both in regulatory compliance and as cost-effective as possible, based on currently available protective wear products. Cleanroom garment processing companies provide their customers with a variety of information on currently available options and regulatory changes.
Previously unconsidered fabric developments also may offer desired advantages. For example, anti-microbial finishes are worth consideration in settings where they have not often traditionally been applied, such as medical equipment production and food processing.
Protection in the Controlled Environment
Where chemical splash protection is needed, garment system components are available with fabric weaves and multilayer designs that form particulate barriers and offer some built-in chemical splash resistance. Non-woven fabric laminated with an impermeable coating also is an option. Items include typical cleanroom wear such as lab coats, coveralls, aprons, pants, hoods, bouffant caps, sleeve protectors, boot covers and gloves. If the risk assessment indicates more than light splash protection is needed due to potentially difficult-to-control chemical flow or vapor eruption, reusable options include durable, coated, plastic material with minimal, liquid-tight or taped seams and Velcro fasteners.
Commonly used fabrics for molten splash protection include either synthetic-based weaves or blends of wool and other fibers.
The level of protection afforded by a garment is indicated via testing for resistance to, or permeation by, various chemicals according to standards (F903 or F739) established by ASTM International (American Society for Testing and Materials). Keep in mind, however, that these standards do not necessarily address every safety concern of an individual situation or every possible failure point of a particular garment system.
Reusables or Disposables: Today's Choices
Consumable (disposable) cleanroom wear is worn once, then disposed of in a landfill or via incineration. Disposal can be costly, and pre-use internal costs such as shipping and distribution to designated sites add to the expense. The life of a reusable cleanroom garment, on the other hand, will often be about 5 years. For companies using cleanroom wear on a daily basis, a survey by a cleanroom garment processing firm showed that changing from disposables to reusable garment systems could reduce costs by nearly 30 percent.
Of course, each situation is different and reusables may not be the best option. For example, in a research and development setting, cleanroom wear may be used just once a month or less and disposable wear could be more cost-effective.
Cleanroom garment processing companies that provide and maintain reusable garments can provide information about garment system options and their costs for the sake of comparison and evaluation of future needs.
Maintaining Reusable Cleanroom Garments
Whether reusable garment processing takes place at a garment rental and processing facility, or at a manufacturer's on premise laundry, the process requires advanced technology and must begin with inspection to ensure that any garments in need of repair are tracked to receive needed repairs prior to processing. Garments also must be sorted for specific processing based on requirements of the controlled environment in which they are worn, and according to any contamination that has occurred. If chemical contamination has occurred, chemical degradation of the fabric is possible and may necessitate disposal of the garment.
Laundering in a pass-through washer system permits soiled linens to enter through one side and come out the other after cleaning, with lower air pressure on the soiled side ensuring that microorganisms do not flow through and contaminate clean garments. Water used in the cleanroom garment wash process must be treated using methods such as ultrafiltration, reverse osmosis or radiation to kill bacteria. Drying, folding and packaging and quality assurance testing also must take place within the controlled cleanroom garment processing environment.
Every site operated by a cleanroom garment processor should be ISO-certified. Other requirements include garment traceability and contingency planning for exposure of the facility to unexpected contaminants. Check with your provider to ensure these conditions are met.
In situations involving cleanroom wear contaminated by potentially toxic substances such as cleaning chemicals, fertilizers, pesticides, herbicides or pathogens, cleanroom garment processors use proven wastewater management practices to avoid washing pollutants into water systems. Thus, these companies help reduce the environmental impact of washing contaminated items.
David Hobson is president of the Uniform & Textile Service Association (http://www.utsa.com), an international trade organization that represents these companies and works to convey information about new uniform textile options. He can be reached at [email protected].