The work that P1-P4 laboratory can undertake is also divided according to the safety level, and its strict level is from low to high.

 

P1 laboratory: basic laboratory, suitable for low harm to human body, animals and plants or environment, without pathogenic factors to healthy adults, animals and plants.

 

P2 laboratory: basic laboratory, suitable for pathogenic factors with medium or potential hazards to human body, animals, plants or environment, which will not cause serious harm to healthy adults, animals and environment, and has effective prevention and treatment measures.

 

It is suitable for the prevention and treatment of animal, plant and human diseases in the laboratory, and it is also highly harmful to the environment.

 

P4 laboratory: the highest level protection laboratory, which is suitable for pathogenic factors that are highly harmful to human body, animals, plants or the environment, transmitted by aerosol or unknown, or unknown and highly dangerous. There are no preventive and therapeutic measures. Like Ebola.

 

The construction of biosafety laboratory needs to comply with the published "building technical specification for biosafety laboratory". According to the specifications, P2 laboratory should be equipped with primary and secondary barriers, while P3 and P4 laboratories should be equipped with primary and secondary barriers.

 

The primary barrier ensures the isolation between the operator and the operated object, including the biosafety cabinet and positive pressure protective clothing; the secondary barrier ensures the isolation between the biosafety laboratory and the external environment, including the ventilation system. Therefore, the primary barrier and the secondary barrier are the protective umbrellas for the experimental personnel and the external environment respectively. The technical specifications of the main rooms of P3 and P4 grade laboratories, including the main laboratory, buffer room of the main laboratory, isolation corridor, protective clothing replacement room, preparation room, shower area, etc., are also specified in the building technical specifications. Ultra high cleaning level, constant range of temperature, humidity and pressure difference are the guarantee of experimental safety.

 

You may wonder what the top level P4 laboratory is like?

 

As the highest level of biosafety laboratory, P4 laboratory is a sharp tool to deal with high-risk, and can not prevent and treat the virulent virus. P4 laboratory is generally an independent building. If it shares a building with other biological laboratories, it also needs to occupy an independent isolation area in the building and be completely isolated from other nearby buildings. In the common four layer structure, the first layer is the sewage treatment and support equipment, the second layer is the core experimental area, the third layer is the exhaust pipe filter layer, and the fourth layer is the air conditioning equipment and supply and exhaust pipe.

 

When entering the ordinary laboratory, the experimenters only need experimental clothes, gloves and face protection equipment. However, there are potential risk factors in high-level experiments. How can researchers protect themselves?

 

As we mentioned earlier, the primary barrier ensures the isolation of laboratory personnel from potentially toxic bacteria. Before entering the high-level laboratory, personnel need to go through multiple procedures, including external changing room, shower room, internal changing room, buffer room, etc. it may take 20-30 minutes to enter the laboratory from the outside. Therefore, the laboratory staff need to receive strict training before going on duty, and must ensure to follow the use process after going on duty. In order to isolate researchers from potential pathogens, they need to wear positive pressure protective clothing with independent oxygen supply. In the protective clothing, the air that the experimenters breathe comes from the independent air system, and the breathing tube needs to be replaced when they move in the laboratory, which is why there are many spiral tubes hanging in the laboratory.