Objectives. This research intends to investigate the responsibilities of the parties engaged in the implementation phase of the infrastructure projects in occupational health and safety, i.e., the consultant and contractor. Methods. A questionnaire was developed through the selection and modification of the responsibilities from the literature review. Results. The statistical analysis results show that the consultants and contractors both ranked the item �The owner requires the contractor to implement the occupational safety standards within the bid� first in the owner responsibilities, having 0.67 relative importance index (RII). In the responsibilities of the consultant, the first ranked item was �The consultant has a role in adopting occupational safety plans and contingency plans�, having 0.66 RII. In the responsibilities of the contractor, the first ranked item was �The contractor shall provide the insurance cover for all project crews�, having 0.71 RII. In the responsibilities of the workers, the first ranked item was �Workers know the handling of tools and equipment within the project�, having 0.59 RII. Conclusion. Overall, there was general agreement between consultants and contractors to classify and arrange items because both face the same conditions and have the same working environment. © 2021 Central Institute for Labour Protection�National Research Institute (CIOP-PIB).