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       Cleanrooms are a group of special facilities with special requirements for infrastructure, environmental monitoring, staff capacity and hygiene. Author: Dr. Patricia Sitek, owner of CRK
       The growing presence of controlled environments in all areas of industry creates new challenges for production personnel and therefore expectations for management to implement new standards.
        Various data show that more than 80% of microbial incidents and dust exceedances are caused by the presence and activities of personnel in cleanrooms. Indeed, ingress, replacement and handling of raw materials and equipment can result in the release of large quantities of particles, resulting in the transfer of biological agents from skin surfaces and materials into the environment. In addition, equipment such as tools, cleaning products and packaging materials also have a significant impact on the functionality of the cleanroom.
       Since personnel are the largest source of contamination in cleanrooms, it is important to ask how to effectively reduce the spread of living and nonliving particles to meet ISO 14644 requirements during personnel movement into the cleanroom area.
       Use appropriate clothing to prevent the spread of particles and microbial agents from workers’ body surfaces to the surrounding work area.
        The most important factor in preventing the spread of contamination in cleanrooms is the selection of cleanroom clothing appropriate to the level of cleanliness. In this publication we will focus on reusable garments rated ISO 8/D and ISO 7/C, describing the requirements for materials, surface breathability and specific design.
       However, before we look at the cleanroom clothing requirements, we will briefly discuss the basic ISO8/D and ISO7/C cleanroom personnel requirements.
        First, to effectively prevent the spread of contamination in a cleanroom, it is necessary to develop and implement in each cleanroom a detailed SOP (Standard Operating Procedure) that describes the basic principles of cleanroom operation in the organization. Such procedures must be written, implemented, understood and followed in the user’s native language. Also important in preparation is the appropriate training of personnel responsible for operating the controlled area, as well as the requirement to conduct appropriate medical examinations taking into account the hazards identified in the workplace. Randomly checking employees’ hands for cleanliness, testing for infectious diseases, and even regular dental checkups are just some of the “fun” that await newcomers to the cleanroom.
        Entry into the cleanroom is through an airlock, which is designed and equipped to prevent cross-contamination, especially along the entry path. Depending on the type of production, we divide the airlocks according to increasing degrees of cleanliness or add shower airlocks to the clean rooms.
        Although ISO 14644 has fairly relaxed requirements for ISO 8 and ISO 7 cleanliness levels, the level of contamination control is still high. This is because regulatory limits for particulate matter and microbial contaminants are so high that it is easy to give the impression that we are constantly monitoring pollution. This is why choosing the right clothing for work is such an important part of the pollution control plan, meeting not only comfort expectations, but also design, material and breathability expectations.
        The use of protective clothing can prevent the spread of particles and microbial agents from workers’ body surfaces to the surrounding work area. The most common material used to make cleanroom clothing is polyester. This is due to the fact that the material is highly dust-proof and at the same time completely breathable. It is important to note that polyester is a recognized material having the highest ISO purity level, as required by the CSM (Cleanroom Suitable Materials) protocol of the Fraunhofer Institute.
        Carbon fiber is used as an additive in the production of polyester cleanroom clothing to provide additional antistatic properties. Their amount usually does not exceed 1% of the total mass of the material.
       Interestingly, while choosing clothing color based on cleanliness level may not have a direct impact on contamination monitoring, it can improve work discipline and monitor worker activity in the cleanroom area.
       According to ISO 14644-5:2016, cleanroom clothing must not only retain body particles from workers, but just as importantly, be breathable, comfortable and resistant to fragmentation.
       ISO 14644 Part 5 (Annex B) provides precise guidance on functionality, selection, material properties, fit and finish, thermal comfort, washing and drying processes, and clothing storage requirements.
       In this publication, we will introduce you to the most common types of cleanroom clothing that meet the requirements of ISO 14644-5.
        It’s important to note that ISO 8 rated clothing (often called “pajamas”) must be made from carbon fiber-infused polyester, like a suit or robe. Caps used to protect the head may be disposable, but their functionality is often reduced due to susceptibility to mechanical damage. Then you should think about a reusable lid.
        An integral part of clothing is shoes, which, like clothing, must be made of materials that are mechanically resistant and resistant to the release of dirt. Typically rubber or equivalent material meeting the requirements of ISO 14644.
       In any case, if the risk analysis shows that at the end of the dressing procedure, protective gloves are worn to minimize the spread of contamination from the worker’s body into the work area.
       After use, reusable clothing is sent to a clean laundry facility where it is washed and dried under ISO Class 5 conditions.
       Since ISO classes 8 and ISO 7 do not require post-sterilization of clothing, the clothing is packaged and sent to the user immediately after drying.
       Disposable clothing does not need to be washed and dried, so it is necessary to handle it and establish a waste disposal policy within the organization.
        Reusable clothing can be used for 1–5 days, depending on what is developed in the contamination control plan after a risk analysis. It is important to remember not to exceed the maximum time that clothing can be safely used, especially in manufacturing areas where microbial contamination control is required.
        Properly selected clothing that meets ISO 8 and ISO 7 standards can effectively block the transfer of mechanical and microbiological contaminants. However, this requires reference to the requirements of ISO 14644, conducting a hazard analysis of the production area, developing a contamination control plan and implementing the system with appropriate employee training.
       Even the best materials and best technology will not be fully effective unless the organization has internal and external training systems in place to ensure that the appropriate level of awareness and responsibility is developed in adhering to the pollution control plan.