Lower exhaust ventilation cabinet of oil gas detection shelter mobile laboratory

A lower air exhaust ventilation cabinet of an oil gas detection shelter mobile laboratory comprises a cuboid cabinet body, the interior of the cabinet body is divided into an upper part and a lower part by an experiment table arranged in the horizontal direction, the upper space of the cabinet body is in the shape of a right trapezoid with the narrow upper portion and the wide lower portion, and the front face of the upper space of the cabinet body is an inclined face of the right trapezoid. The lower part of the cabinet body is a cuboid space and is provided with a funnel-shaped air duct, an exhaust fan and a soft air duct; a bottom plate through hole is formed in the bottom plate of the cabinet body; and an air outlet pipeline at the lower part of the exhaust fan penetrates through the bottom plate through hole and extends to the outside. A button switch is arranged on a front panel of the lower space of the cabinet body. A power line of the exhaust fan is connected with the button switch in series and then