This Bureau of Mines report describes a new type of scrubber (dust collector) and ventilation system built into the auger support frame (boom) of a Jeffrey 120l continuous mining machine. With this twin scrubber arrangement, one scrubber is mounted into each side of the boom. Each scrubber includes a 2,500-cfm fan, a flooded fibrous-bed scrubber panel, and a water droplet eliminator. The system was designed for minimum size and adds only a few inches to machine height. Exhaust duct design allows flexibility with various airflow configurations to suit both blowing and exhaust face ventilation systems and brattice distances ranging up to 20 feet. Full-scale tests with exhaust ventilation were conducted at a Mine Safety and Health Administration surface facility at Bruceton, Pennsylvania, to determine the scrubbers' methane dilution capability. Several configurations of the twin scrubber-ventilation system produced striking improvements in face methane dilution when compared with conventional systems.