Holcim's Siggenthal works in Switzerland has restarted its cement production with an activated carbon filter after the equipment was badly damaged in a fire in February. The fire was attributed to self-igniting coal dust, which first led to a smouldering fire on 16 February and then developed in an open fire, damaging the activated carbon filter.

The repair and reconstruction of the 55m-high building took around five months and included preventative measures. The rebuilding has also seen the revision of the existing steel structure.

However, thanks to the works' conventional gas cleaning systems, output was not interrupted during the reconstruction. But the verified emission values during this period without the activated carbon filter exceeded specified limits.