According to its function and safety level, the laboratory can be divided into four levels, which are P1, P2, P3 and P4 laboratories.

P1 Laboratory: This is a basic laboratory, which is suitable for situations with low hazards to humans, animals and plants or the environment, and does not have disease-causing factors. Such laboratories are often used to manipulate microorganisms that do not normally cause disease in humans or animals.

P2 laboratory: suitable for moderately harmful or potentially dangerous pathogenic factors, but will not cause serious harm, with effective prevention and treatment measures. P2 laboratories are very widely used biosafety class laboratories for handling microorganisms that can cause disease in humans or animals, but generally do not pose a serious hazard to humans, animals or the environment.

P3 laboratory: Suitable for highly hazardous agents that can transmit serious or even fatal diseases to humans through direct contact or aerosols, usually with preventive and therapeutic measures. Such laboratories are used to manipulate microorganisms capable of causing serious diseases in humans or animals, and are relatively easily transmitted directly or indirectly from person to person, animal to person, and animal to animal.

P4 Laboratory: This is a high level protective laboratory, suitable for highly hazardous, through aerosol transmission or transmission route unknown, unknown highly dangerous pathogenic agents, no prevention and treatment measures. The P4 laboratory is a high-level global biosafety laboratory, which is suitable for handling pathogenic agents that are highly harmful to humans, animals and plants or the environment, such as Ebola virus and smallpox virus.

These laboratory grades are based on the hazard levels of the subjects and operations and the biosafety precautions required.