Most basic protocol programs for cleanrooms are based on the Institute of Environmental Science and Technology (IEST) recommended practices for contamination control and the ISO 14644 series of international standards for cleanrooms and associated controlled environments. The focus of any protocol program is to protect the integrity of the cleanroom and the products and processes in the cleanroom from the people working in the cleanroom. Whereas contamination may be due to the product, processes, or equipment in the clean-room, the people working in the cleanroom exercise the greatest control over the cause of and elimination of contamination. Therefore, all protocol programs address the functionality of the cleanroom, the behavior of the people working in the cleanroom, and the cleaning and maintenance of the cleanroom.
The basic components of abalanced cleanroom protocol program are:
- The facility design and cleanroom floor-plan
- Cleanroom gowning requirements and procedures
- Personnel behavior within the cleanroom environment
- Cleanroom supplies – correct types and usage
- Cleanroom housekeeping
- Continuous improvement and assessments (audits and trending test results)
FACILITY DESIGN
Initially,
one must understand the design, layout, and certification of the
cleanroom. IEST-RP-CC012.2, “Considerations in Cleanroom Design”
is an excellent document to reference for understanding the design
and functions of various components in cleanrooms (i.e., air flow,
room pressures and particle management, etc.). Appendix B, “Sample
cleanroom construction protocol” provides protocol guidance to
cleanroom construction employees during the four levelsof cleanroom
construction. This IEST recommended practice supports ISO 14644-4,
“Clean-roomsand associated controlled environments – Part 4:
Design.” Since 1999,cleanrooms have been certified to ISO 14644-1,
“Cleanrooms and associatedcontrolled environments – Part 1:
Classification of air cleanliness” andISO 14644-2, “Cleanrooms
and associated controlled environments – Part2: Specifications for
testing and monitoring to prove compliance with ISO 14644-1.
CLEANROOM GOWNING PROCEDURES
After
the cleanroom has passed certification, cleanroom personnel must don
the required cleanroom apparel applicable to the classification of
the cleanroom. IEST-RP-CC003.3 contains a chart of recommended
gowning configurations and frequency of change of garments based on
the Air Cleanliness Classes of ISO 14644-1. Many clean-room
operations require the cleanroom personnel to change from street
clothes to 100% polyester building suits or tech suits to reduce the
amount of particle contamination in the cleanroom environment. The
garment system selected must meet the specifications for the
clean-room applications. Facility requirements for changing areas,
lockers, in-use garment storage, soiled garment storage, garment
inventory storage, and internal inventory transit must be defined.
Additionally cleanroom garment laundering and othergarment management
services must be defined and subcontracted.
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. At work, all employees must wash hands before entering the cleanroom and after eating and/or using the toilet. Cleanroom compatible hand cream may be applied prior to gowning.