Disinfection and sanitation of clean areas: Part 1
Cleaning | Clothes
Regular and well-planned disinfection is crucial for a rapid response to microbiological incidents. Here, Patrycja Sitek of CRK discusses how to achieve the most optimal economic result and without danger for clean processes and areas.
Specialized cleaning cloths are used in many areas of industry to keep surfaces clean by mechanical removal of dust and biological contamination. Modern materials and the method of production make it possible to reduce the amount of disinfectants used, while achieving the same effects of removing bioparticles. In clean rooms, special cleaning cloths are used to effectively remove bacteria, fungi and viruses from the surface.
Dusts and biological pollutants, identified in the ISO8-ISO7 cleanroom classes, present a serious risk of failure of the manufacturing process or of experimental research. The environmental monitoring carried out to confirm the microbiological and dusty cleanliness of the air and surfaces serves the early detection of potential threats as well as the development of effective methods of removing pollutants by mechanical surface removal and disinfection.
Among the biological factors that can actually affect the experimental or production process, we can distinguish TAMC (Total Aerobic Microbial Count) and TYMC (Total Yeasts / Molds Count) – i.e. aerobic bacteria and fungi, which are determined on the basis of tests confirming their presence on the surfaces or in the product after an incubation time of between 48 and 72 hours. In addition, in the case of some ISO8-ISO7 laboratories classified according to BSL 3-4 requirements, an important consideration in choosing specialist cleaning cloths is the risk of surface contamination by dangerous biological agents, including viruses.
In the context of dust pollution, an important element of monitoring is the prevention of contamination of the product and the environment by particles of 0.5 to 5.0 microns. Devices called particle counters are used to monitor the degree of air pollution by particles. Particles that fall to the surface can also transmit microbial contamination, so effective removal of these particles greatly reduces the risk of cross-contamination. In areas where production activities are carried out, activities in the field of risk analysis and validation of the decontamination process are carried out in order to confirm the effectiveness of the activities. Validation activities also include qualification processes for cleaning and disinfection agents as well as cleaning cloths and mop covers. Parameters such as:
- structure and material composition of the cleaning cloth
- the degree of release of particles from the surface
- percentage of pollutants eliminated
- the effect of the cleaning cloth used on the reduction of bio-pollutants
- certificates attesting to the possibility of using it in a clean room
- the possibility of sterilization of waste
The disinfection process is designed to eliminate microorganisms and their spores. Disinfection destroys the vegetative forms of bacteria and fungi and shows some effectiveness against viruses. Optimizing the selection of suitable cleaning cloths for ISO8 classes is also associated with the selection of suitable absorbent cloths, characterized by the appropriate structure and type of fibers, while not generating the risk of environmental contamination. of production.
Guides to good manufacturing practice or good laboratory practice not only deal with disinfection and removal of microorganisms from the surface, but also indicate the need to maintain appropriate microbiological limits, regular monitoring of the environment and rotation of agents used for disinfection. At the same time, the Health Council of the Netherlands published in December 2016 a report entitled “Resistance due to disinfectants”, which indicates that the incompetent, too frequent and abundant use of disinfectants is a direct cause of the mutation of environmental strains. of microorganisms. , including viruses, and becomes causes resistance to disinfectants, especially strong oxidizing agents such as chlorites. ANNEX 1 EU-GMP requires the effective disposal of disinfectant residues as well as debris. It also states that chemical contamination during the disinfection process should be minimized.
In subjecting the provisions of the report to further analysis, the following conclusions should be drawn:
- Too frequent use of disinfectants, especially in so-called critical areas, generates a high concentration of the agent on a given surface per unit of time.
- It is not necessary to constantly use wipers with disinfectant liquid, called “Ready to use”.
- Appropriate disinfection of surfaces and devices, while reducing the frequency of use of the disinfectant, is sufficient to maintain the appropriate level of microbiological purity.
- Finally – washing the surface with a cloth of suitable quality soaked in purified water or, in justified cases, sterile, gives effects similar to the use of a disinfectant and has a real impact on the amount of disinfectant used .
Modern specialty cleaning cloths are designed and manufactured in such a way as to allow the effective removal of bio-contamination from the surface with a minimal amount or without the use of disinfectant.
The mechanism of the effectiveness of such an action is strictly linked to the mechanical elimination of the microbiological film, and more precisely to the elimination of bacterial, fungal and viral biomass. The aquatic environment is only one element perfecting this process. The way the fabric is made is of utmost importance in this case. Specialized materials for wiping wet and dry surfaces are characterized by a structure that provides the finest split microfibers, the diameter of which is divided into several dozen segments, thus ensuring excellent efficiency of over 99.9% for eliminate bacteria from the surface and 99.51% for virus elimination, including viruses belonging to the same family and generic group as SARS-CoV-2. The test method used to verify the effectiveness of cleaning cloths of the highest class is based on the standard EN 16615: 2015. It is based on a quantitative evaluation used to assess the bactericidal and yeasticidal activity on surfaces not porous with mechanical action with the use of cloths in the medical field (the so-called four-field test). These wipes have different contents of polyester, polyamide and viscose in their structure, so as to ensure maximum absorption and collection capacity of microbial contamination with a minimum level of residual particles.
The technology of cleaning cloths for their safe use of wet and dry services with obtaining results comparable with the use of disinfectants.
Regular and well-planned disinfection is crucial for a rapid response to microbiological incidents. At the same time, well-designed SOPs for mechanical cleaning and high-quality cloths will respond to an optimal, economical and safe result for clean processes and areas.