A chamber apparatus for reducing the speed of particles carried in a pneumatic conveyor conduit includes a chamber with an inlet port in the chamber, the inlet port adapted for attachment to the pneumatic conveyor conduit, and an outlet port in a lower portion of the chamber. A plurality of flexible bristles is secured at ends thereof to a wall of the chamber and extend into the chamber such that particles carried in an air stream entering the inlet port contact the bristles. The chamber is configured such that particles falling inside the chamber move out of the chamber through the outlet port.