A wet-type dust collector for use at the return end of tunnels or hard headings. It may be either 6,000 ft₃/min or 12,000 ft₃/min (2.8 m₃/s or 5.7 m₃/s) in capacity. It wets and traps dust as it passes through the appliance, and releases it in the form of a slurry, which is removed by a pump. The microdyne is bolted to the outby end of the exhaust pipe, and the auxiliary fan is bolted to the outby end of the dust collector.