How to safely use laboratory fume hoods?

Laboratory fume hood is an indispensable part of laboratory furniture. Utilize the effects of exhaust and ventilation in the laboratory. During experimental operations, various harmful gases, odors, moisture, flammable, explosive, and corrosive substances are generated, which are qualitative. In order to protect the safety of users and prevent pollutants from spreading to the laboratory during experiments, fume hoods should be used near pollution sources.
In recent years, in order to improve the experimental environment, experiments on all steel fume hoods have gradually shifted to fume hoods, which requires fume hoods to have functions suitable for equipment use. Especially for most newly built laboratories that require air conditioning, the number of fume hoods used should be included in the air conditioning system plan during the preliminary design phase of the building. Due to the important role of fume hoods in biochemical laboratories, the use of fume hoods has increased sharply in terms of improving laboratory environment, improving labor hygiene conditions, and enhancing work efficiency.

Laboratory fume hoods can be divided into three types based on different exhaust methods: upper exhaust, lower exhaust, and simultaneous upper and lower exhaust. In order to ensure uniform wind speed in the work area, the ventilation cabinet during the cooling process should use lower exhaust, and the ventilation cabinet during the heat process should use upper exhaust. In the process of unstable heat, exhaust ports can be set up both up and down according to the changes in heat inside the cabinet, and the ratio of upper and lower exhaust can be adjusted to obtain uniform wind speed.
Laboratory fume hoods are divided into three categories based on their air intake methods. The indoor intake cycle and exhaust to the outside is called full exhaust, which is a widely used type.
According to different usage states, the fume hood can be divided into integral lower open type, floor standing type, double-sided type, three sided glass type, desktop type, and connected type. It is designed specifically for radiation testing, synthesis testing, and chloric acid testing according to different experimental needs.
Safety is the mission of laboratory fume hoods. The use of fume hoods in laboratories is to ensure the safety of users and prevent pollution to the surrounding environment.
Attention should be paid to safety when using laboratory fume hoods:
Before starting the experiment, it is necessary to confirm that the fume hood is in operation before proceeding with the experimental operation.
Before the end of the experiment, it is necessary to continue running for at least 5 minutes to turn off the ventilation fan and exhaust the residual gas in the pipeline. It is also possible to consider installing an exhaust time delay device to ensure delayed operation of the ventilation fan.
During the experiment, do not place any equipment within 150 millimeters of the glass window. Large experimental equipment should have sufficient space and should not affect air flow. The front window should be closed as much as possible.