Safety issues impact construction workforce and industry, for example by generating extra costs and delays. Achieving planned levels of productivity is crucial for the overall success of a construction project. Despite improvements in equipment and workplace ergonomics, the construction industry is still characterized by physically demanding activities and stressful environments. Excessive physical strain on the workers leads to decreased productivity, inattentiveness, poor quality work, accidents, and injuries. Therefore, a Physical Demand Monitoring System (PDMS) able to assess physical strain through a combined analysis of workers physiological parameters (e.g., heart rate) and environmental conditions (e.g., temperature) may be an important step towards better safety and productivity management. In previous studies of physiological demands in construction the instrumentation hindered the workers activities. However, now less invasive technologies are available for this purpose. The scope of this project is to establish the framework of a PDMS able to operate in real construction situations.