CleanBoy® Plus – a particle- and germ-free cleanroom workbench for all medical-technical applications

Table 1: Microbial count determination in the environment and in the CleanBoy® Plus workbench

Everyone who cares about their health knows this common truth: germs are everywhere and omnipresent in the ambient and indoor air. Germs are the smallest biological living units, visible only under a microscope. Due to their particle size of a few micrometers, they can remain airborne for a long time and maintain their biological activity. They can not only alter and destroy products, as we know from yeasts and molds, but also cause significant health damage, especially in medical and pharmaceutical products, if they remain undetected or untreated. Only through proper cleaning of the air can airborne particles and thus germs be removed from the air. Filter technologies have proven particularly effective because they offer an inexpensive and operationally cost-effective alternative and can be retrofitted later, e.g., by using laminar flow boxes. However, in applications within medical-technical fields, reducing germs alone is not sufficient, because a sterile environment must first be created and maintained through appropriate hygiene measures, which will be explained below.

1. Hygiene Measures in Medical Technology

Medical technology is increasingly advancing the medical care of patients. Many diagnostic and therapeutic advances have only become possible through corresponding technical procedures and developments. The importance of hygiene becomes clear, as even years ago, nearly half of all infections acquired by patients in hospitals were associated with or caused by medical-technical measures. Medical progress involves the use of increasingly complex technical aids/devices, which can also pose risks to staff during application, processing, and cleaning. Additionally, there is a rise in resistant germs, which have long been detectable in our environment, demanding our special attention. So, what must we do to protect products in medical and pharmaceutical technology from germs?

2. Prevention of Germ and Particle Entry through Air Filtration

As already mentioned, germs are omnipresent in ambient and indoor air. Only proper cleaning of the air can remove germs from the air. Cost-effective filter techniques and the use of laminar flow boxes have proven particularly effective.

The CleanBoy® Plus is such a laminar flow box, developed by Spetec GmbH, a specialized company with over 20 years of experience in building filter systems, including for needs in medical and pharmaceutical technology. Its core is a high-performance filter of the type HEPA H14 with an efficiency of 99.995%, meaning the filter removes at least 99.995% (99.9995%) of all particles and germs at a particle size of 0.12 μm (0.3 μm). The box was tested by the Fraunhofer Institute for Production Technology and Automation (IPA), certified according to DIN standard EN ISO 14644, and classified as ISO 5. With the H14 filter, the Spetec CleanBoy® Plus has an isolation factor of 10,000, which means the air quality in the work area is improved by at least a factor of 10,000 compared to the surrounding air.

Similar applies to larger cleanrooms. These must be assembled, measured, and subsequently certified on-site by Spetec GmbH. For example, one customer decided to install an entirely particle-free room within an existing manufacturing hall to produce microchips for high-resolution video cameras used in building protection and airport security, ensuring dust-free production.

When assessing indoor air quality in a cleanroom or laminar flow box, it is irrelevant whether the particle is dust, an aerosol, a microbe, a yeast cell, or a bacterium. All these particles can impair the manufacturing of microchips, as their removal depends solely on the particle size and hydrodynamic properties, not on their chemical or biological characteristics. The design of a high-performance cleanroom can be adapted and visualized to the customer's spatial requirements using 3D software. Often, smaller modular units or production lines serve the same purpose. Smaller flow box modules have proven effective here.

The function of a flow box is quite simple. The room air is drawn in by a fan, installed in the upper housing part in the photo, and pushed through a high-performance particle filter (H14). The filter arrangement creates a laminar airflow behind the glass panels in the work area, protecting the product from incoming particles through overpressure.

By combining laminar flow boxes, entire production lines or cleanrooms can be built so that the medical-technical product never comes into contact with particles or germs during manufacturing. The setup, arrangement, and design of individual components can be tailored to the customer's needs.

3. Reduction of Germ Counts

In collaboration with LS SE & Co. KG (Bad Bocklet), germ count measurements were conducted in a CleanBoy® Plus workstation. The germ counts were determined in a manufacturing hall, outside on the company premises, and inside the filter box using a high-volume air germ sampling device (RCS High Flow Touch; 1000 L) on sampling strips. Additionally, swab samples were taken from surfaces, especially inside and on the glass panels of the CleanBoy Plus, and colony-forming units (CFU) were counted. The results are summarized in Table 1.

Furthermore, the CleanBoy® Plus was tested by the IPA and certified as a medical-grade device with cleanliness class B. This means that, according to GMP guidelines, Annex Biocontamination, no more than 5 CFU should be detectable on sedimentation plates (diameter 90 mm) after 4 hours of operation within the cleanroom workstation.

4. Prevention of Biofilms

However, it is not enough for a device to filter out germs from the surrounding air to qualify as a medical-grade device. Precautions must also be taken to prevent the colonization of germs within the work area. Regular hygiene measures must be performed by the customer before restarting and during operation, including cleaning surfaces, disinfecting surfaces, and disinfecting or sterilizing all work tools in the workstation. All surfaces inside and outside the workstation are smooth or polished or designed to prevent biofilm formation easily. All surfaces are made of stainless steel or glass. Corners and edges are rounded, and transitions between materials are sealed to prevent nesting. All materials used are resistant to common disinfectants or cleaning agents as specified in hygiene plans. After installation, we offer a sterilization check and germ load measurement in the workstation and on surfaces, as well as regular inspection and maintenance of all components.

Summary

The CleanBoy® Plus is a cleanroom workstation designed for work in a germ- and particle-protected environment, specifically developed for the manufacturing and processing of sterile pharmaceuticals, medical-technical products, or for sterile storage and packaging of medical-technical products. It is suitable for use in hospitals, medical practices, and pharmacies and is also applicable in clinical laboratories, wherever sterile and germ-free products are to be manufactured, packaged, stored, or analyzed. The products are protected from invading germs and particles by a filtered laminar airflow. The materials used and the surfaces are designed to meet special hygiene requirements, which is why the cleanroom workstation has been certified as a medical-grade device.