How to Properly Use a Centrifuge in a Biosafety Laboratory

　　In a biosafety laboratory Centrifuge In terms of applicable standards, the integration of “General Requirements for Biosafety in Laboratories” and “General Requirements for Biosafety in Veterinary Laboratories” produces a synergistic effect, complementing each other perfectly. In particular, the “General Requirements for Biosafety in Veterinary Laboratories” provides detailed guidelines on centrifuge selection and auxiliary laboratory design. From these guidelines, we can at least identify the following three key points:

　　1) Centrifuges should be as tabletop and compact as possible, facilitating operation inside a biosafety cabinet when necessary (Note: This refers to “microcentrifuges” that correspond to “large centrifuges,” not miniature, handheld, pocket-sized centrifuges).

　　Reason: The higher the rotational speed during centrifugation, the greater the capacity of the rotor used or the larger the centrifugal radius, the stronger the aerosol formation effect during centrifugation.

　　2) If the existing centrifuge cannot be miniaturized, the accompanying rotor must be equipped with a sealed lid.

　　Because it better meets the requirements of biosafety operating procedures, the biosafety airtight suit should be prioritized over the standard version.

　　3) When using large-scale centrifuges, a negative-pressure enclosure must be provided for or custom-designed for the centrifuge and connected to the laboratory’s exhaust ventilation system (Note: This refers to vertical low-temperature high-speed centrifuges or vertical ultracentrifuges).

　　Regarding the use of negative pressure enclosures.

　　Safety requirements for the use of centrifuges in biosafety laboratories:

　　1. Operate the centrifuge according to the operation manual.

　　2. The placement height should allow even shorter-statured staff members to see inside the centrifuge. Laboratories can be categorized into three types based on their affiliation: The first type comprises laboratories that are affiliated with or administered by universities; the second type of laboratory is under the jurisdiction of national institutions, some of which are even international organizations; and the third type of laboratory is directly affiliated with industrial enterprises, serving the development and research of industrial technologies.

　　3. Centrifuge tubes and containers used to hold centrifuged samples should be made of thick-walled glass or, preferably, plastic (composed of synthetic resin, plasticizers, stabilizers, and pigments). Before use, check carefully to ensure that they are free from damage.

　　4. Test tubes and specimen containers used for centrifugation should always be securely capped (screw caps are preferred).

　　5. The loading, balancing, sealing, and opening of centrifuge buckets must be performed inside a biosafety cabinet.

　　6. The centrifuge buckets and cross shafts should be paired according to their weights and properly balanced after the centrifuge tubes have been loaded.

　　Centrifugation is a critical step in risk prevention and control in biosafety laboratories that cannot be overlooked. However, both the “Manual” and China’s laboratory biosafety regulatory documents only stipulate that pathogenic microbial samples must be centrifuged using sealed rotors; yet, there has been no explicit mention whatsoever of criteria for assessing the sealing performance of these rotors. Moreover, none of these documents refer to the national standard “Safety Requirements for Electrical Equipment Used in Measurement, Control, and Laboratories—Part 2-020: Specific Requirements for Laboratory Centrifuges” (GB 4793.7-2008) or to the IEC 61010-2-020 standard. By contrast, regulations concerning the architectural layout and airflow patterns of biosafety laboratories clearly specify the relevant national standards and norms upon which they are based.