Contrary to other methods FMECA is founded on the humanization of the data since it is a work group which determines the numerical values of the study. So whatever the type of industry, the definition of the work group is fundamental in FMECA. This characteristic makes it possible to support exchanges between the various actors of the project and to exploit their knowledge of them. The choice of the participants is essential for the unfolding of FMECA. With this intention, the following criteria are to be considered: competence, quantity, diversity, the organizer, training, and softwares.