Detected and reported accidents with and without absenteeism as well as near misses and unsafe situations are analyzed according to a standard procedure by safety experts referring to possible causes of accidents. It is recommended to develop methodically a cause-effect diagram in addition to the analysis because this graphical representation of causes, which can lead to an incident, enables a simple and structured investigation of the accidents. By the method of the cause-effect diagram (RCA) all causes of the effect should be recorded and mapped and not only the one main cause. Furthermore, with this approach it is possible to acquire different solutions afterwards. Such a RCA can be very simple or very detailed, depending on the matter. Basically each analysis consists of the following tree steps. The results of the investigation are documented accordingly. In the case of determination of safety-related, occupational health, or organizational deficiencies during the inspections and investigations at the site of occurrence, they must be stopped immediately to avoid further similar incidents. Furthermore, the work-related risk assessment has to be checked on its validity and if necessary further corrective and preventive measures have to be developed in accordance to the relevant procedure.