Medical Device & Diagnostic Industry Magazine
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An MD&DI  February 1998 Column

CLEANROOM STANDARDS

ISO TC 209 anticipates completing documents relating to cleanrooms and controlled environments before the year 2000.

Investment in cleanrooms has greatly increased during the past decade, largely because of the financial and quality-related benefits provided by controlled environments. The increased usage of such environments is expected to continue as the emphasis on the miniaturization of components and on the control of biocontamination persists.

International companies using controlled environments—as well as those considering such uses—have been aware of the apparent need for global standards in this area. It is this apparent need that has led to the creation of the International Organization for Standardization's (ISO) Technical Committee 209 and its subsequent accomplishments.

BACKGROUND

In 1992, at the urging of the Institute of Environmental Sciences, the American National Standards Institute petitioned ISO to create a technical committee on cleanrooms and associated controlled environments. This new committee, ISO TC 209, was formally established in May 1993. Its mission is to develop an international standard for cleanrooms and associated controlled environments that encompasses the standardization of equipment, facilities, and operational methods, while also defining procedural and operational limits and testing procedures to minimize contamination.

Manufacturers require varying levels of controlled environments, as seen in these class 100,000 (top), 10,000 (circle) and class 1 (bottom) facilities. Photos courtesy of Richard A. Matthews
 

Thirty-four countries are currently active in ISO TC 209. Voting members, referred to as "P" nations, are Australia, Belgium, China, Denmark, Finland, France, Germany, Italy, Jamaica, Japan, Korea, The Netherlands, Norway, Portugal, Russia, Sweden, Switzerland, the United Kingdom, and the United States. Nonvoting members, referred to as "O" nations, are Bulgaria, the Czech Republic, Egypt, India, Ireland, Malaysia, New Zealand, the Philippines, Poland, Saudi Arabia, South Africa, Thailand, Turkey, Ukraine, and Yugoslavia.

In accordance with ISO procedures, all work by the technical committee is performed in working groups for which specific parameters have been defined and established. Additionally, committee work is to be voted by consensus, trade barriers are to be eliminated, and criteria for cleanrooms and related environments are to be standardized. The committee will not define cleanrooms by user-specific application nor by microbial limits, and no standard will be instituted if it has a major negative economic impact on a particular nation. Table I lists ISO TC 209's seven working groups and their respective convenors.

Table I. ISO TC 209's seven working groups, their subject areas, and convening countries.

COMMITTEE ACTIVITIES

Since the committee's inception in 1993, cooperation among P nations has been exceptional, resulting in the rapid development of global cleanroom standards. Below are brief summaries outlining the status of each working group as of December 31, 1997.

Working Group 1. ISO 14644-1, "Classification of Air Cleanliness," is in final draft status (FDIS), and it's conceivable that it will become the first formal international standard produced by ISO TC 209. Three new classes have been added to the existing standard, Federal Standard 209, two cleaner and one dirtier (Tables II and III).

Tables II and III. TC 209 comparisons showing that three classes have been added in ISO 14644-1.

ISO 14644-2 on specifications for testing and monitoring is currently a draft international standard (DIS) and is available for comment. This document specifies the requirements for monitoring a cleanroom or clean zone to provide evidence of its continued compliance with ISO 14644-1 for the designated classification of airborne particulate cleanliness. A schedule of normative and informative tests is included in the document. Depending on the backlog and production schedules at ISO's headquarters in Geneva, the formalization of ISO 14644-1 and 14644-2 will probably occur late this year.

Working Group 2. ISO 14698-1, "Biocontamination Control General Principles," was elevated to DIS status last October and will be available for comment early this year. This document describes the principles and basic methodology for a formal system to assess and control biocontamination. It will include the general requirements of a sampling plan; target, alert, and action levels; qualification; and reporting.

ISO 14698-2, "Evaluation and Interpretation of Biocontamination Data," was also elevated to DIS status last October and will be available for comment early this year. This document describes the basic principles and methodological requirements for all microbiological data evaluation and the estimation of biocontamination data obtained from sampling for viable particles. It will also include evaluation of the initial monitoring plan and of the data resulting from routine monitoring, as well as analysis of the data, trending, and record keeping.

Working Group 3. This working group on metrology and testing methods expects to have a final draft to the technical committee for review in the first quarter of 1998. Performance tests are specified at operational phases—as-built, at-rest, and operational. The items to be measured are categorized as either primary or user-optional tests. Primary tests include particle count, airflow velocity, airflow volume, pressure differential, and installed filter leakage. User-optional tests include flow visualization, airflow parallelism, airflow turbulence, temperature, humidity, molecule contamination, electrostatic charge, particle fallout, recovery, and integrity.

Working Group 4. ISO TC 14644-4, "Design and Construction," was elevated to DIS status in October 1997 and will be available for comment early this year. This document specifies requirements for the design and construction of cleanroom and clean air devices, as well as requirements for start-up and qualification. It also provides guidance on the basic elements of design and construction.

Working Group 5. The cleanroom operations working group estimates that a final draft will be completed by the fourth quarter of this year. Topics to be addressed include entry/admittance, procedures, and cleaning, as well as maintenance as it relates to equipment, materials, and people.

Working Group 6. In detailing terms, definitions, and units, the definitive document of this working group must include all definitions from all approved documents of ISO TC 209. Consequently, it will be the final ISO TC 209 document.

Working Group 7. The minienvironments and isolators working group expects a final draft to be completed by the fourth quarter of this year. This document will specify the performance requirements for minienvironments, isolation systems, and associated transfer devices, with a focus on how these systems differ from conventional cleanrooms in the areas of monitoring, design, testing, material compatibility, integrity, biocontamination, and so on.

STATUS OF FEDERAL STANDARD 209

While standards in Europe have traditionally been organized on a national basis, the development of a single market in the European Union has made it essential to have European—as opposed to national—standards. The European Committee for Standardization (CEN) was established for this purpose, and CEN standards now take precedence over existing national standards. In many cases, a national standard may be withdrawn when a CEN standard is developed.

With the formation of ISO TC 209, an agreement was reached with CEN to accept these standards by allowing parallel voting within CEN and ISO. ISO 14644-1 has been accepted by CEN and is in the final stages of ISO approval. Thus, this document will become a requirement for all companies selling into Europe.

From a U.S. perspective, Congress has passed a law stating that it is not necessary to maintain a federal standard, such as Federal Standard 209, if a national standard exists. As noted earlier, the formalization of ISO 14644-1 and 14644-2 will probably occur in late 1998, after which time they will become American National Standards and there will be no reason to maintain Federal Standard 209.

WHAT'S NEXT

ISO TC 209's schedule for completing global cleanroom standards is ambitious. To date, 50% of the standards are complete, and completion of the full family of documents is expected by the year 2000. The committee and many of its working groups will meet in Phoenix during the annual meeting of the Institute of Environmental Sciences and Technology (IEST) in April. This meeting is expected to be the largest technical event of the decade, combining the IEST meeting with the International Committee of Contamination Control Societies' International Symposium on Contamination Control and the Symposium on Cleanrooms for the Healthcare Industry (which is jointly sponsored by IEST and the Parenteral Drug Association).

CONCLUSION

Companies are increasingly willing to invest in cleanrooms to take advantage of their controlled environments. The popularity of cleanrooms accentuates the need to develop global standards for their components as well as biocontamination and quality issues.

Anne Marie Dixon is managing partner at Cleanroom Management Associates, Inc. (Carson City, NV). Richard A. Matthews is president of Filtration Technology, Inc. (Greens-boro, NC). For more information on TC 209 or the symposia in April, contact IEST, Mt. Prospect, IL, at 847/255-1561.

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