OhdAB is a classification system for activities and requirement levels in professional situations, developed on the basis of historical occupational titles. The system comprises a five-level hierarchical classification model, ranging from a broad summary of ten occupational areas to a very fine-grained distinction between approximately 1,900 occupational categories. At the same time, approximately 46,000 occupational names are standardised, with each name given in a gender-neutral, female and male spelling. The taxonomy is available in both German and English, with the historical occupational titles translated using Deepl and only partially adapted. FactGrid also offers other languages, which were also generated using AI technologies.
The OhdAB system is fundamentally based on the 2010/20 classification of occupations by the Federal Employment Agency [KldB 2010 – Statistics of the Federal Employment Agency (Federal Employment Agency 2021)]. OhdAB has based its methodology on the KldB for recording and measuring similarities between occupational activities on the basis of skills and professional expertise on the one hand and requirement levels on the other. This enables a comparison between historical and modern occupational worlds and the linking of modern national and international standards. At the same time, KldB 2010 establishes concordance with the international standard ISCO-08 ([https://ilostat.ilo.org/methods/concepts-and-definitions/classification-occupation/ ISCO]), older versions of KldB and other relevant vocabularies and analysis tools. It also provides a translation of modern occupational standard designations into English.