Safe laboratory ventilation device

The utility model provides a safe laboratory ventilation device, relates to the technical field of laboratory ventilation, and aims to solve the problems that the existing laboratory ventilation device is used for ventilating the whole laboratory, so that targeted ventilation on an experiment on a certain experiment table is difficult to realize, and the ventilation efficiency is high. In order to solve the problems that gas generated in an experiment in a laboratory can be discharged after being treated, the gas generated in the experiment can be directly discharged, and the ecological environment is harmful, the device comprises a pipeline, the left end of the pipeline is fixedly connected with a flange plate, the cross section of the pipeline is in an L shape, a filter layer is movably connected in the pipeline, and a sealing plate is installed at the position of the filter layer. The sealing plate is hinged to the pipeline, the right side of the filtering layer is provided with a turbofan, the turbofan is