A dust control apparatus and method for a bulk material handling transfer system having a chute comprising a pathway there through for handling varying volumes of bulk material flowing through the chute using gravity flow. A self-adjusting air restrictor gate is mounted in the chute for engaging the upper surface of flowing bulk material through the chute for restricting the air pathway during material volume flow variations to reduce dust emissions. The gate member contacts the upper surface of flowing bulk material and moves up and down in response to the flow of bulk material through the chute to restrict the flow of air to reduce dust. A counterweight mechanism and a damper helps maintain controlled contact of the air restrictor gate with the upper surface of bulk material flowing through the chute.