The literature on occupational safety shows that the main safety concerns focus on physical, interpersonal and organizational aspects. Plus, there are studies that indicate experience and knowledge transmission as important aspects for the preservation of health and safety at work. A case study was conducted, in a Portuguese chemical industry, to identify workers’ concerns on safety at work, and, to understand whether experience or knowledge transmission are considered in these concerns. Data was collected through the Technique of Free Association with 43 workers. A descriptive analysis and content analysis of the data were carried out. Results allow the identification of seven types of safety concerns (some are common concerns) and show that workers’ experience and knowledge transmission are, in fact, considered as a concern. This underpin the originality of this study and contribute to complement occupational safety perceptions, particularly in studies in industries considered dangerous, such as chemical industry.