New Standard for Cleanrooms and Controlled Environments
Ben Van Houten
After 10 years of research and development, the International Organization for Standardization (ISO; Geneva) has released a Final Draft International Standard (FDIS) for cleanrooms and associated controlled environments.
ISO, in collaboration with the Institute of Environmental Sciences and Technology (IEST; Rolling Meadows, IL), issued ISO/FDIS 14644-7, Cleanrooms and associated controlled environmentsï¿½Part 7: Separative devices (clean air hoods, gloveboxes, isolators, and minienvironments), last month.
In developing the standard, the ISO working group considered the needs of different industries and introduced the term separative devices. That term includes all configurations from open unrestricted air overspill to wholly contained systems. Common terms-of-trade such as clean air hoods, gloveboxes, isolators, and minienvironments have different meanings depending on the industry in which they are used.
With that backdrop, this section of the ISO 14644 series provides a generic overview and specifies the minimum requirements for the design, construction, installation, testing, and approval of separative devices ranging from open to closed systems. ï¿½This is an overarching, unifying document for all industries using separative devices,ï¿½ says David Ensor, a U.S. consultant. ï¿½A common set of terminology resulting from this effort will greatly improve communications within the industry.ï¿½
In addition to the United States, other members of the working group represented Belgium, Finland, Germany, Italy, Japan, Korea, Russia, Switzerland, and the UK. The document is currently in balloting by these nations, and if approved will be issued as a formal ISO standard later this year.
ISO 14644-7 was developed from a so-called ï¿½blank sheetï¿½ of paper, since a precedent-setting document had not previously existed. The working groupï¿½s original orders were to define performance requirements in areas of minienvironments and isolators. The document specifies the minimum re-quirements for the design, construction, installation, testing, and approval of separative devices in those respects where they differ from cleanrooms. These requirements focus on the ways that minienvironments differ from cleanrooms in the areas of monitoring, design, testing, molecular contamination, material compatibility, integrity, and microbial contamination.
In addition, a number of policy decisions were made during the final draftï¿½s development. First, a common set of process requirements was identified, setting this equipment apart from cleanrooms. It is clear that these devices exist to create conditions that cannot be found in a cleanroom. For example, personnel typically work outside these devices and manipulate tools, processes, and products inside with access devices such as glove systems and automatic robots.
Annex A of the document presents a nomenclature of separation approaches to describe various configurations. Annex D provides examples of transfer devices by configuration. Additional annexes cover systems for air handling and gas, access devices, and leak detection and testing.
According to IEST, the limitations of Part 7 are:
ï¿½ Application-specific requirements are not addressed.
ï¿½ User requirements are as agreed by customer and supplier.
ï¿½ Specific processes to be accommodated in the separative device installation are not specified.
ï¿½ Fire, safety, and other regulatory matters are not considered specifically; the appropriate national and local requirements shall be respected.
ï¿½ Full-suits are not within the scope of this standard.
The document is designed for use as a trade reference per agreement between a customer and supplier. Copies are currently available from IEST, and can be ordered from the organizationï¿½s Web site, www.iest.org.