Abstract Introduction Work-related diseases are increasing and considered a global health challenge. Meanwhile, work-related risk factors and diseases are not equally distributed across occupational groups. Previous work health interventions have not succeeded in reducing the prevalence of work-related diseases. Therefore, integrated approaches combining prevention of disease and promotion of health in work health interventions have been developed. The aim of the Integrated Approach to Health, Wellbeing, and Productivity at Work (ITASPA) intervention was to prevent work-related injuries and diseases and promote the health, safety and wellbeing of cleaners. Methods The ITASPA intervention was implemented at two Danish workplaces among cleaners. At each workplace a committee of employees was established to develop their own initiatives to promote the health of the workers. By use of the British Medical research Council’s framework, a process evaluation was conducted. Qualitative data (focus group interview and field notes) and quantitative data (questionnaires) of participants evaluated the implementation. Results A total of 91 cleaners participated in health checks, and three workshops were held at each workplace. The development and implementation of activities was affected by mechanisms, such as lack of information about the intervention, new power dynamics, and lack of motivation for behavior changes, and contextual factors, such as many replacements, time pressure and absence of managers. Conclusions Integrated approaches in work health interventions among employees with short or no education may positively impact employees’ health, wellbeing and safety if comprehensively implemented. However, attention should be drawn to interventions that adapt a participatory design, as unintended power dynamics may occur when employees are given the tasks of implementing behavior changes among colleagues. The role of managers to obtain successful implementation should be highlighted.