Metering laboratory and low-noise ventilation system thereof

The invention relates to a metering laboratory and a low-noise ventilation system thereof.The metering laboratory comprises a draught fan and a ventilation pipe connected to the draught fan, a connecting mechanism for connecting the ventilation pipe with the draught fan is arranged between the ventilation pipe and the draught fan, and the connecting mechanism comprises a bent pipe connected to the draught fan and a flexible pipe arranged on the bent pipe; one end of the bent pipe is connected with the draught fan, the other end of the bent pipe is vertically and upwards arranged and connected with the flexible pipe, the end, away from the bent pipe, of the flexible pipe is connected with the ventilation pipe, the end, connected with the flexible pipe, of the ventilation pipe is horizontally arranged, and a plurality of supporting rings are arranged in the flexible pipe in the length direction of the flexible pipe. A gap is reserved between every two adjacent rings, and the lower ends of the flexible pipes are