We are building an ISO Class 7 (formerly Class 10,000) modular cleanroom on our university campus. Our students will wear bouffants, shoecovers, and frocks. Is there a gowning protocol for frocks? We also need procedures for cleaning the modular cleanroom and working in the cleanroom.
There are four key factors that contribute to contamination in all cleanrooms or controlled environments. The furniture and/or equipment, the product being produced, the processes performed in the cleanroom, and the people working inside the cleanroom. The people working in the cleanroom contribute the most contamination; however, the people working in the cleanroom exercise the most control over the environment of the cleanroom. Selecting the correct garments and performing the recommended garmenting procedures will increase the contamination control in the cleanroom.
GOWNING PROCEDURE FOR FROCKS
Gowning procedures begin at home with daily bathing or showering, shaving, brushing of teeth and hair, and application of non-silicone containing skin moisturizers to reduce skin flakes. All make-up, hair gels, hair sprays, perfumes, aromatic after-shave lotions or body lotions are not cleanroom compatible and therefore unacceptable to wear to work in a cleanroom. Your students must wash their hands before entering the cleanroom and after smoking, eating, and/or using the toilet. Cleanroom compatible hand cream may be applied prior to gowning.
The gowning protocol for frocks is similar to the donning and doffing of coveralls. All hair is completely covered inside a bouffant including the ears, and if required, a beard cover is used to cover all facial hair. Even if a student has a shaved head, a bouffant must be worn to prevent contamination from the scalp. The shoes are covered with shoe covers. If static electricity is a concern, there are ESD shoe covers. If you are concerned with slips, trips, or falls inside the cleanroom, there are non-skid shoe covers available. If static electricity is a concern, ESD frocks are available. When donning a frock, it is imperative that the outside surface does not touch the walls, floor, or other operators. The frock is carefully removed from the cleanroom compatible, static dissipative, plastic bag by grasping the inside surface of fabric of the frock just below the collar on the back and allowed to unfold. The inside of the frock is folded back at the shoulders to protect the outside surface from contamination during donning. The right arm is placed inside the right sleeve to the full length of the sleeve. The left arm is placed inside the left sleeve to the full length of the sleeve. The frock is pulled onto the shoulders and the zipper is pulled to the full length of the zipper and/or all snaps are snapped. Some operations will require gloves to be worn over the hands and wrist areas. The glove should overlap the wrist cuff area of the frock. Some cleanroom facilities have operators that fail to comply with appropriate cleanroom gowning protocol. The sleeves are pushed and/or rolled up the arms. The front panels of the frock are open, often partially unzipped or unsnapped. Therefore, your students should be trained thoroughly and periodically monitored for compliance.
When doffing the frock, it is imperative that the outside surface does not touch the walls, floor, or other operators. The frocks worn in ISO Class 7 and 8 cleanrooms are often hung on hangers or hooks during the work week. This area should be clean and preferably under a HEPA filter. The HEPA filtered air will remove some particles and fibers during storage.
PERSONNEL PRACTICES IN CLEANROOMS
In all cleanroom classifications, the personnel should follow recommended behavior practices inside the cleanroom. Examples of recommended cleanroom behavior from IEST-RP-CC027, “Personnel, Practices, and Procedures for Cleanrooms and Other Controlled Environments” are:
- Only trained, authorized personnel are allowed inside the cleanroom.
- Movement inside the cleanroom should be deliberate and slow. Operators should not lean over the product during production. No running is allowed.
- Operators should not engage in any activity that could contaminate the garments or work surfaces. No horseplay is allowed.
- Cleanroom frocks do not have pockets. Operators may not reach inside or under the frock to obtain objects from street clothes.
- Frocks must be changed immediately if they become contaminated during the production process.
- Nothing is allowed inside the cleanroom complex which is not required in the cleanroom manufacturing process. This includes personal items such as jewelry or keys, cosmetics, tobacco or matches in any form, and food or drink in any form. Hair may not be combed in the cleanroom gowning area. NOTE: It is recommended that smokers drink at least 8oz. of water after smoking and before entering a cleanroom.
- Only cleanroom compatible ball-point pens are allowed inside the cleanroom for recording data on cleanroom compatible paper and clipboards.
- While working in the cleanroom, avoid mannerisms such as scratching head or rubbing hands.
- The use of facial tissues is prohibited in the cleanroom. If one must use a cleanroom compatible non-linting tissue, it must be used only in the gowning area and disposed of appropriately in a waste receptacle.
- All doors must remain closed when not entering or exiting. Emergency doors may be alarmed with a visual and audible alarm to enforce compliance
- If there are any changes such as skin irritations, open sores, or respiratory infections, the personnel should be reassigned to non-cleanroom duties.
CLEANROOM SUPPLIES AND STORAGE
Garments may be stored inside the cleanroom gowning area as well as the many cleanroom consumable supplies to support the cleanroom operators and the processes inside the cleanroom. Cleanroom supplies should be stored in cleanroom packaging until use. All chemicals and supplies used to clean the cleanroom should also be stored in original cleanroom packaging until use. Used mops and mop heads should be properly disposed of after use. It is recommended that the cleanroom supplies storage area be ventilated under vertical unidirectional air flow. Prior to introduction of any supplies into the cleanroom storage areas, proper wipe down of the exterior packaging should be performed.
An integral piece of the cleanroom management program is cleaning the cleanroom. IEST-RP-CC018, “Cleanroom Housekeeping” details aspects of proper cleaning of the cleanroom, selection of cleaning materials, equipment, and cleaning agents as well as auditing the cleaning of the cleanroom. A documented and controlled cleanroom cleaning program should be established and maintained to ensure the integrity of the cleanroom environment. Selection of cleanroom cleaning materials, equipment, and cleaning agents should be appropriate to the type of cleaning required and compatibility with all surfaces in your modular cleanroom. All cleaning agents and subsequent cleaning protocols should be validated to assure efficacy of cleaning.
CONTINUOUS MONITORING FOR EFFICACY
Environmental monitoring and auditing the modular cleanroom assures that the documented procedures and protocols are understood, implemented, and effective. The audit program should provide documented and impartial evidence that the modular cleanroom is functioning as originally designed. Tracking and trending this data will show shifts in the program which can be addressed prior to compromising the cleanroom.
Additional information for your students is summarized in IEST-RP-CC026, “Cleanroom Operations” which is a supporting document for ISO 14644-5, “Cleanrooms and associated controlled environments – Part 5: Operations”. Appendices A-F provide information on the various operations in the cleanroom from garmenting and behavior to entry, cleaning, and movement of equipment.
Jan Eudy is Corporate Q.A. Manager for Cintas Corporation and President-Emeritus and Fellow of the Institute of Environmental Sciences and Technology.