OCRA

Introduction: the OCRA method

The OCRA method is a widely adopted approach for analysing workers’ exposure to tasks featuring various upper limb (UL) risk factors like repetitiveness, force, awkward postures and movements, lack of recovery periods, and others . This methodology has been approved as best practise by the International Ergonomics Association (IEA) to monitor and predict the risk of upper limbs WMSDs, the most frequently reported cause of injury among european workers (source) . Nowadays, OCRA is adopted by over 30'000 technical specialists in Europe , like OSH operators, ergonomists and production engineers, guiding them to re-design organisational and physical workspace improving both productivity and operators' health in the long run.

Application

Despite its sophistication, this methodology is very time-consuming demanding several days to train operators in recognise and collect data regarding different MSDs risk dimensions: for this reason this procedure can be adopted only by experts who want to properly re-design the operators tasks. Furthermore, as the user will see in the following chapters, this methodology gives high relevance to the relationship between the duration of a task and the risk associated to it, deeply penalising manual processes in which the Cycle Time is equally distributed among tasks i.e. mounting/dismounting operations involving a limited set of screwdrivers.

For this reason, the OCRA method has been applied in a wide portfolio of industrial cases in the manufacturing and service sector, where jobs involving repetitive movements and/or efforts of the upper limbs were heterogeneous and complex. Main examples: Manufacture of mechanical components, electrical appliances, automobiles but also cloth textile and food processing.

This guide will support future users to understand the theoretical concepts concerning the OCRA methodology and will clarify the main steps for their adoption in the digital toolkit.