Building a cleanroom-Start with ISO 14644-4


By Anne Marie Dixon, Cleanroom Management Associates, Inc.

If you spend a significant portion of your career in cleanroom technology, you will have the opportunity to design, build or renovate a cleanroom. Before beginning any design or project, a key concern of any user is the general use of the facility-the operation to be performed and the requirements. Product, process, regulatory, and quality issues must be defined and these parameters will establish the methods of control as well as the cleanliness and monitoring requirements of the cleanroom. The ISO 14644-4 standard details items that will be needed for planning and design, construction and start-up, testing and approval, and documentation of a cleanroom project. The focus of the standard is to specify the requirements for the design and construction of a cleanroom installation; however, it does not prescribe specific technological or contractual means to meet these requirements. Construction guidance is provided, including the requirements for start-up and qualification. In general, the basic elements of design and construction needed to ensure continued satisfactory operation are identified through the consideration of relevant aspects of operation and maintenance.

Annex A of ISO 14644-4 describes contamination control zones. These concepts are depicted as basic sketches that will assist the user in the determination of types of airflow, segregation (people and process), and pressurization. Annex B suggests the type of cleanroom by industry and fundamental design criteria (i.e., healthcare facilities and microelectronic facilities).

The layout and configuration of any cleanroom must support the relevant equipment, process, product, safety, quality, personnel and material movements. The design, therefore, is a coordinated effort to accommodate all the issues pertinent to the research or manufacturing that will take place in the space. In any planning process, the development must include: cost, outside factors, construction, time lines, design options, environmental controls, and other factors.

Annexes B through G offer guidance in these areas as well as filtration, vibration, and energy conservation. The above sections assist the user in Design Qualifications (DQ) to ensure that the facility, when completed, will be suitable for the intended purpose. The requirement or need for DQ can be debated; however, with the accelerating cost of cleanrooms, designing and building without this approach could pose a significant risk.

After a design has been qualified and accepted, proper planning will allow for controlled construction, start-up and testing of a facility. Construction work, by nature, creates and generates particulates, which must be reduced and removed during this phase. The “clean-build” system in this ISO standard addresses methods for controlling the risk of unwanted contamination during construction. Commissioning, functional testing, acceptance testing and documentation are required prior to any operational start-up.

Annex H of this standard is a 13-page checklist of items that could impact the functionality of the cleanroom. The checklist allows the user to effectively communicate with the designer regarding the requirements for the process, equipment, external factors, systems and other issues that influence the cost, scheduling, and basic design of a cleanroom and other controlled environments. The checklist details the following categories:

Process requirements

Process contaminants

Process equipment specifications

External factors

Environmental requirements


System redundancy

Operations and maintenance

Personnel, ergonomics, aesthetics

Future developments



Review of requirements, standards, occupancy states, and management

Carefully following the guidance terms spelled out in Annex H is a must for anyone designing, building or operating clean space.

The checklists found in the standard provide the user a litany of the small and large details that could be forgotten or overlooked in any cleanroom project. Thinking about a new facility? Start with ISO 14644-4-a small investment in time and cost.

ISO 14644-4 is available on the IEST Web site (, or by telephoning IEST at (847) 255-1561.

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Anne Marie Dixon is the president of Cleanroom Management Associates, Inc., a consulting firm that specializes in competitive benchmarking, training, and auditing of clean and aseptic operations and management. Ms. Dixon has been actively engaged in the field of contamination control for over 25 years and has extensive experience in the areas of training, technical writing, strategic consulting, facility start-up, construction protocols and process optimization. She is the Past President of the IEST, and was awarded the grade of Fellow by IEST in 1998. She chairs the United States Technical Advisory Group to ISO/TC 209 and is head of the U.S. Delegation for ISO/TC 209. Widely published with over 100 technical articles and four books, she offers technical courses for IEST, PDA, CCE, IIR, IDEMA, and other associations.

About IEST: Founded in 1953, IEST is an international not-for-profit technical society of engineers, scientists and educators that serves its members and the industries they represent (simulating, testing, controlling, and teaching the environments of earth and space) through education and the development of recommended practices and standards. IEST is an ANSI-accredited standards-developing organization; Secretariat of ISO/TC 209, Cleanrooms and associated controlled environments; Administrator of the ANSI-accredited US TAG to ISO/TC 209; Administrator of the ANSI-accredited US TAG to ISO/TC 142, Cleaning equipment for air and other gases; and a founding member of the ANSI-accredited US TAG to ISO/TC 229, Nanotechnologies.