How to choose the right biosafety airtight transfer window?

When choosing a suitable biosafety airtight transfer window, the following aspects need to be considered:
Application scenarios and protection levels:
Biosafety laboratory: Select based on the grade of the laboratory. For example, in BSL-3 and ABSL-3 laboratories, airtight (E1) transfer Windows with disinfection (C1, C2) functions can generally be selected. The BSL-4 and ABSL-4 laboratories require airtight (E2) transfer Windows and disinfection type (C1, C2) at the same time.
Medical and health institutions: Isolation wards in infectious disease hospitals, central laboratory departments, etc., usually choose transfer Windows with good airtightness and disinfection functions to prevent the spread of pathogens.
In the pharmaceutical industry, for sterile drug production workshops and vaccine production workshops, it is necessary to select transfer Windows that can meet the cleanliness requirements of the production environment, and have airtightness and disinfection functions, to ensure the quality and safety of drugs.
Air tightness performance:
Testing standard: According to relevant standards, when the internal pressure attenuation method of the box is adopted for testing after the internal pressure of the box reaches -500 Pa, the natural attenuation of negative pressure within 20 minutes should be less than 250Pa. For places with higher requirements, it may also be necessary to refer to stricter leakage rate standards. For example, under a pressure of -500 Pa, the leakage rate should be less than 0.5% vol/h.
Sealing structure and materials: Select transfer Windows that use high-quality sealing materials, such as silicone rubber, ethylene propylene diene monomer (EPDM) rubber strips, etc. At the same time, the structural design of the door is also very important. For instance, mechanical compression-type doors or inflatable airtight doors, as well as the design of air lock chambers with double-layer door structures and intermediate sealing chambers, can better ensure the airtight effect.
Disinfection function:
Disinfection method: Select a transfer window with an appropriate disinfection method according to your needs. If the C1 type transfer window is equipped with ultraviolet lamps inside, it is suitable for general disinfection of the air, walls, and surfaces of objects. Model C2 is equipped with an inlet and outlet for disinfection gas (vapor), which can be connected to external disinfection devices such as hydrogen peroxide gas generators, etc. It can achieve more efficient and thorough disinfection and is suitable for scenarios with high disinfection requirements.
Disinfection effect verification: The transfer window should have the function of verifying the disinfection effect to ensure that the disinfection process can achieve the expected killing rate. If the killing rate of indicator bacteria is ≥99.9%, it is judged as qualified.
Material and Structure:
Material: The transfer window doors and inner cavities are generally made of 316L stainless steel to meet the requirements of corrosion resistance and disinfection. Other components can be selected from 2mm thick 304L stainless steel. It is recommended to use 316L stainless steel for the embedded frame to ensure long-term stable use in environments such as biosafety laboratories.
Structural design: The inner cavity should be integral-formed, with weld seams polished, and the polishing degree should be less than 0.4μm. The corners should be smooth, facilitating cleaning and disinfection, and preventing the growth and residue of microorganisms. The viewing window on the door is made of explosion-proof and fire-resistant glass with a thickness of more than 5mm, which not only meets the observation requirements but also ensures safety.
Interlock function
Mechanical and electronic interlocking: Airtight transfer Windows should be equipped with mechanical and electronic interlocking devices to ensure that only when one side of the door is closed can the other side be opened during the transfer of items, preventing air circulation and cross-contamination caused by the simultaneous opening of both sides. Meanwhile, within the set disinfection time, the doors on both sides of the transfer window cannot be opened to ensure the effectiveness of the disinfection process.
Size and capacity: According to the actual usage requirements, select the appropriate size and capacity of the transfer window to meet the size and quantity requirements of the transferred items. At the same time, the space size of the installation position of the transfer window also needs to be considered to ensure its smooth installation and use.
Brand and after-sales service: Choose well-known brands and suppliers with good after-sales service. Their products are usually more guaranteed in terms of quality, performance, and stability. In addition, good after-sales service can provide timely repair and technical support when the transfer window malfunctions, ensuring its normal operation.
Cost-effectiveness: Under the premise of meeting the usage functions and safety requirements, comprehensively consider the initial investment and operating costs of the transfer window, including equipment prices, installation, and commissioning fees, operating energy consumption, maintenance costs, etc., conduct a cost-effectiveness analysis, and select products with high-cost performance.