How to achieve precise environmental control and effectively prevent microbial contamination in biotechnology cleanrooms?

How to achieve precise environmental control in biotechnology cleanrooms?
1.Airflow control
  Airflow control is a key component of environmental control in a biological cleanroom. By filtering the air with a HEPA air filter (HEPA) or an ULPA air filter (ULPA) and maintaining a positive pressure environment, particulate matter and microbial contamination that enters and is generated inside the room can be effectively reduced. In addition, depending on the cleanliness level, unidirectional or turbulent airflow modes can be selected. Unidirectional air flows in a laminar manner in a single direction, effectively controlling the spread of contaminants; turbulent air is suitable for areas that require high cleanliness but have larger spaces.

2.Temperature and humidity control
  Temperature and humidity control in a biological cleanroom is critical to ensure comfort of staff and proper functioning of equipment. Typically, the temperature should be set between 20-25℃ and the humidity level should be controlled between 40-50%. This can be achieved through a heating, ventilation, and air conditioning (HVAC) system, with a monitoring system to monitor environmental parameters in real time.

3.Differential pressure control
  Maintaining a positive differential pressure between the cleanroom interior and the outside areas can prevent contaminants from entering. This requires an air pressure monitoring system to monitor the pressure gradient in real time and adjust the airflow as needed. At the same time, installing airlocks or other physical barriers can prevent contaminants from escaping when workers enter and exit.

4.Microbiological monitoring
  Microbiological monitoring of biological cleanrooms is an important means of ensuring environmental cleanliness. By creating a laminar airflow pattern and using HEPA filters to purify the air, microbial particles and contaminants can be removed. Setting an upper limit on the allowable microbial concentration and regularly monitoring air quality using a microbial monitoring system can effectively control microbial contamination.

5.Security measures
  Safety measures for biological cleanrooms include developing safety procedures and policies, and providing regular safety training for staff. These measures also include testing the number of dust particles in the cleanroom under static conditions before each production and after a certain production cycle, in order to evaluate and understand the number of dust particles in the cleanroom.

6.Precision control system
  In order to achieve the above-mentioned accuracy of environmental control, a cleanroom environmental condition precision control system can be used. The system includes a condition monitoring system, a central control system, an air supply system, an exhaust system, a return air system and an air handling system. The coordinated work of these systems can ensure that the environmental parameters in the cleanroom are always in a good condition.

How to effectively prevent and control microbial contamination in biotechnology cleanrooms?

1.Prevention and control measures on airflow
Filtration and sterilization:
  Air purification technology uses filtration as the most common way to control microorganisms in the air. Filter media include cellulose, glass wool or artificial fibers. Filtering the air in the entire room (such as a sterile operating room) or a local operating area (such as a clean bench) through an air purification device can effectively remove microorganisms. The HEPA filter has a filtration efficiency of 99.97% - 99.99% or higher, which can effectively remove microbial particles in the air. It is usually installed at the air inlet and outlet of the clean bench.

Chemical disinfection：
  Using disinfectants to act on indoor air, such as using appropriate chemical disinfectants to disinfect the air in biotechnology cleanrooms, can reduce the number of microorganisms. However, attention should be paid to the safety of the utilizing disinfectants and residual issues.
  Ultraviolet irradiation: Use ultraviolet rays to irradiate and disinfect indoor air. When the equipment is not in use or during work breaks, turning on the ultraviolet lamp to irradiate the indoor air. Ultraviolet rays have a killing effect on microorganisms and can reduce the content of microorganisms in the air. However, ultraviolet irradiation has certain limitations, such as ineffective disinfection of places that cannot be irradiated, etc.

2.Water prevention and control measures
  Chemical disinfectants: Chemical disinfectants are commonly used to disinfect process water and have better effects, such as sodium hypochlorite or chlorine gas disinfection. However, it should be noted that there should be no dead corners in the water system that cannot be disinfected.Membrane filtration method: It is suitable for continuous circulation treatment of water systems, which can effectively remove microorganisms in water and ensure that the microbial indicators of process water are qualified.Ultraviolet irradiation method: Ultraviolet irradiation disinfection is applied in water systems. It is suitable for water that requires special treatment (such as high optical transparency requirements), generally before the end. The water treated by this method is odorless and tasteless, and there will be no phenomenon of microorganisms migrating to the filter.
  In actual water systems, these methods are often used in combination and designed and installed in appropriate locations.

3.Prevention and control measures for factory buildings and equipment surfaces
  The interior surfaces of buildings should be impermeable, smooth, without cracks, tight joints, and no loose particles, so as to prevent microorganisms from adhering to and growing on the surface, and should be able to withstand cleaning and disinfection.
  In order to maintain the cleanliness of the cleanroom and prevent it from being contaminated by the adjacent room or contaminating the adjacent room, a higher or lower air pressure difference should be maintained in the cleanroom. The static pressure difference between cleanrooms of different grades should be greater than 5pa, and the static pressure difference between the clean area and the outdoors should be greater than 10pa to prevent backflow.Equipment and pipelines should be easy to disassemble and have a simple structure to facilitate cleaning and disinfection, so as to prevent microorganisms from growing on the surface of the equipment and spreading to the product or production environment. Clean and disinfect the surface of the equipment regularly. Use appropriate disinfectants to wipe or wash the surface of the equipment to remove possible microbial contamination.

4.Personnel prevention and control measures
Personnel hygiene management：
  Human hair and skin can emit microorganisms, and human skin, hands, face, pores, wrinkles and moist areas often have various microorganisms. Therefore, before entering the cleanroom, operators should perform thorough cleaning, such as washing hands and face, changing into clean work clothes, etc.The oral cavity is an area that is more sensitive to contamination, and the water droplets produced by breathing and coughing contain microbial contamination. Therefore, operators should avoid coughing, sneezing, etc. in the cleanroom. If it is unavoidable, they should use appropriate protective equipment (such as masks) to reduce the spread of microorganisms.From washable textiles, lint and starch particles may be emitted, while soft fabrics such as wool may scatter fibers and particles. Pollution may also enter the workplace through shoes. Therefore, operators should wear appropriate clean work clothes, shoe covers, etc., and avoid wearing clothes that are easy to shed fibers or easily contaminated with dust and microorganisms when entering the cleanroom.Cosmetics such as hairspray, perfume, mascara, powder, and jewelry such as earrings, rings, necklaces, and bracelets can spread microbial contamination. Jewelry should be removed before entering the cleanroom and makeup should be avoided.

Operation regulations：
  Operators should strictly abide by the operating principles. For example, when operating on a clean bench, they should wear sterile clothing, use sterile gloves, avoid talking or coughing in the work area, etc., to reduce the risk of microbial contamination caused by human operating errors or irregular behaviors.

5.Prevention and control measures for materials:
  Cleaning and disinfection of materials: Materials entering the cleanroom should be cleaned to remove microorganisms that may be carried on the surface. For some materials that cannot be cleaned, it is necessary to ensure that their sources are reliable and that the microbial indicators meet the requirements.