IEST has responsibility to ISO/TC 209 for convening Working Group 7 and producing an acceptable standard. The standard was developed from a “blank sheet” of paper because a precedence-setting document did not exist. The scope and content has evolved significantly over the last six years.
ISO/TC 209 established WG 7 in late 1994. The first meeting of the working group was held in April 1995. The scope ultimately given to WG 7 in 1995 was as follows:
The scope of the WG 7 shall be to define performance requirements in areas of minienvironments and isolators. These requirements will focus on ways that minienvironments differ from cleanrooms in the area of monitoring, design, testing, molecular contamination, material compatibility, integrity, and microbial contamination.
It was clear from the onset that this standard would be very ambitious from a number of aspects. First, as mentioned, no precedent-setting document existed to match the broad scope of the working group, although some documents existed covering limited parts of the scope.
WG 7 had to define the aspects of how these devices differed from cleanrooms. Therefore, a number of policy decisions needed to be made during the development of the document. First, a common set of process requirements was identified, setting this equipment apart from just “a little cleanroom.” It is clear that these devices, usually located with cleanrooms, exist to create conditions that cannot be found in a cleanroom. Examples include very clean conditions, special atmospheres, and physical barriers to protect workers from hazardous materials. Typically, personnel work outside these devices and manipulate tools, processes, and products inside with access devices. Access devices include manual approaches such as glove systems and automatic robotics handling systems. Transfer devices are used to move material in and out of the device.
Based on the common set of process needs, it was decided to write a single standard. Even though a common technology core exists, the balancing of various industrial needs in the document has proven to take a great deal of work.
The working group name was changed from “Minienvironments and isolators” to “Separative devices” by ISO/TC 209. The name “Separative devices,” while not a perfect description, could be translated without altering the meaning and would not confused with terms used in cleanrooms or other fields. The changing of a name may seem like a very insignificant event; however, it had the effect of allowing the working group drafting the document to focus on the generic aspects of the core technical requirements. The requirements in the standard were written to be completely generic and would apply to all industrial applications. Therefore, the need to write industry-specific annexes became unimportant. The current scope for the draft is as follows:
This part of ISO 14644 specifies the minimum requirements for the design, construction, installation, testing and approval of separative devices in those respects where they differ from cleanrooms as described in ISO 14644-4 and 14644-5. Separative devices range from open to closed systems.
The limitations are:
- Application-specific requirements are not addressed.
- User requirements are as agreed by customer and supplier.
- Specific processes to be accommodated in the separative device installation are not specified.
- Fire, safety and other regulatory matters are not considered specifically; the appropriate national and local requirements shall be respected.
- Full-suits are not within the scope of this standard.