After more than six years of work, the revision of VDI Guideline 3783 Sheet 12 was officially published in November. The WIST group, with Dr Cornelia Kalender and Prof. Rüdiger Höffer, worked intensively on this with colleagues Bernd Leitl, Frank Harms, Rolf-Dieter Lieb, Wolfgang Theurer, Veith Hildebrand, Wolfgang Bächlin and Bernhard Bauhofer in the VDI/DIN Commission on Air Quality Control (KRdL) standards committee. The concept of the guideline was updated, requirements and standards were redefined and new recommendations and comparative data sets were added.