Most companies have systems in place to measure productivity and quality, but few have defined and implemented an "integrated strategy" of quantification and management of the different factors/domains that represent impact for the organization, for example at occupational health level, on development of work related musculoskeletal disorders (WRMDs). Research regarding human performance levels and the development of WRMDs, mainly have been focused on the job/workstation. However, to develop interventions and monitor changes in the Production System a multidimensional approach (micro/macro) is required. The goal of this article is to contribute for the understanding of different factors/domains of the Human-Work System, as well as ways for monitoring the different developments/changes and "impacts" that occur in such System. The presented Case Study, regarding the automotive industry, addresses the implementation of active surveillance tools, namely the adapted version of the Nordic Musculoskeletal Questionnaire, the QuickDASH Questionnaire and the Work Compatibility Model. The goal is to minimize the level of uncertainty, providing indicators to support decision-making at management/operational level contributing for a Lean Performance. The results achieved in two different plants revealed priority production areas/domains that required intervention. These case study approaches try to contribute to monitor/understand the "Loss value" factors and impacts over time in the Organization.