Abstract: The invention concerns a method for the removal of a part (41, 55) of a particle collecting device (40, 41, 42, 55), which part is loaded with at least highly flammable particles (51). The part (41, 55) is removed from a process gas cleaning device (100) of an additive manufacturing device (1) by means of the following steps. An inert gas (50, 250) which substantially encloses the particles (51) is provided. The part (41, 55) of the particle collecting device (40, 41, 42, 55), is removed from the process gas cleaning device (100), wherein the particles (51) remain enclosed in the inert gas (50, 250).

Abstract: A passivation device for passivating filter residues of a filter device arranged in a process gas circuit of an additive manufacturing apparatus includes a reaction unit having an inlet suitable for supplying an oxidant, a coupling unit adapted to be coupled to the filter device for introducing filter residues into the reaction unit, a discharge unit suitable for discharging passivated filter residues from the reaction unit, and an energy supply unit suitable for effecting a reaction between the filter residues and the oxidant in the reaction unit.