| Symbol | Typ | Titel |
|---|---|---|
| B | SK | PERFORMING OPERATIONS; TRANSPORTING |
| B04 | KL | CENTRIFUGAL APPARATUS OR MACHINES FOR CARRYING-OUT PHYSICAL OR CHEMICAL PROCESSES |
| B04B | UKL | CENTRIFUGES (high-speed drum mills B02C 19/11) |
| B04C | UKL | APPARATUS USING FREE VORTEX FLOW, e.g. CYCLONES (exhaust or silencing apparatus for machines or engines having means for removing solid constituents of exhaust, using inertial or centrifugal separators F01N 3/037; cyclonic type combustion apparatus F23) |