The rising awareness of psychosocial risks at workplace means that it is ever more important to prepare methods to assess psychosocial factors in occupational environment. This project of north west tuscany area has the aim to realize an instrument for a gradual risk assessment for this kind of factors without the support of specialists. A decisional flow chart helps to approach the risk assessment step by step on the basis of company features, management and organization problems and company symptoms of stress. The final assessment combines the evaluation of perceived risks with job analysis realizing a matrix containing 5 risk levels, which suggests the priority of preventive measures. The intermediate level (level three) represents the activation level for the medical surveillance. This experience means a proposal for a quantitative assessment of psychosocial risks at workplace.