Abstract. Many construction work tasks are physically very strenuous and the incidence of work-related musculoskeletal disorders (WMSDs) among construction workers is considerably higher than those in most other occupations. The aim of the study presented in this paper was to contribute to understanding a healthy construction site brought about by the best practices implemented by large construction sites to prevent WMSDs. A triangulation method made of interviews, site observations and studies on company"s documents was used to identify the best practices in 13 several construction projects. A range of the best practices both in the pre-construction and construction phases of the projects were identified in six different areas of the balance of the construction workplace system; however, there seems to be a significant need for good practices in the management of a systematic work environment. It is now established that Swedish construction industry has several best practices to protect work-related musculoskeletal health. However, inadequate worker participation and the neglect of health and safety issues by designers in the planning process as well as the implications of some remuneration methods on the production schedule were perceived as detrimental to the musculoskeletal health of construction workers.

Purpose -The purpose of the paper is to investigate how health and safety gains and improvements of the construction workplace can be made through the use of three-dimensional (3D) and four-dimensional (4D) visualization technologies. Design/methodology/approach -The methodology used in the paper was a combination of semi-structured interviews with five construction project planners from three construction projects and observations of a 4D model used in one of the three projects. Findings -The findings of the paper have shown a great potential for 3D and 4D visualization in terms of communicating construction information as well as the health and safety risks in the design process where clash detection, work tasks sequence, workspace congestion can be identified by project stakeholders who are thus able to plan for alternative solutions to reduce or eliminate rework, heavy material handling and repetitive and awkward postures which expose workers to musculoskeletal injury risk.Research limitations/implications -The 3D and 4D models as they are currently used in the design of construction projects, particularly in the three projects investigated in this paper, still lack the worker reference frame and the visual interaction between the worker and the permanent as well as the temporary works. Originality/value -The paper describes the current and emerging trends in the development of 3D, virtual reality and 4D computer-aided design visualization and simulation, which have affected or are likely to have an impact on construction projects planning in the Swedish construction sector.

Research conducted among general contractors in South Africa investigated the impact of the general 10 stages of projects on construction ergonomics (Smallwood 2002). Respondents were required to respond relative to a fi ve-point scale ranging from a minor

Many of those working on construction sites are exposed to demanding work loads; construction workers lift and carry heavy materials and work in awkward postures. Occupational injuries and accidents due to poor ergonomics are more common in the construction industry and many times lead to human tragedies, disrupt construction processes and adversely affect the cost, productivity, and the reputation of the construction industry. In Sweden, it is reported that concrete workers have the highest relative work-related musculoskeletal injury frequency. Therefore, the use of ergonomic production methods to prevent this can have a significant human, social and financial impact. Research introduced here presents a case study of comparative analyses of ergonomic situations for concrete workers performing concrete casting processes. Three different ergonomic risk assessment methods were used to assess the physical strain, hand-arm vibration and noise affects risks involved in concrete casting work tasks. The combination of technical and managerial factors results in a system where workers are as efficient and safe as possible during their work tasks, and thus, makes the construction work environment sustainable. The aim of our research is to find practical methods to evaluate and compare two different concrete casting methods from an ergonomic perspective. The focus is on the production of cast-in-place concrete bridge constructions where the traditional concrete casting method is compared with the SCC (Self-Compacting concrete) casting method. To be able to identify work-related musculoskeletal injury risks due to concrete casting work tasks, QEC (Quick Exposure Check for musculoskeletal risks), PLIBEL (Checklist for identification for Ergonomics Hazards) and ErgoSAM (Ergonomic production technology method) methods were used. Ergonomic risks analysis methods QEC, PLIBEL and ErgoSAM have all shown capabilities to evaluate construction work activities and thus determine whether a construction work activity constitutes a musculoskeletal risk to the worker or not before any ergonomic intervention is introduced. As a result the present ergonomic risks emanating from work methods used in the traditional concrete placing can be significantly reduced with the use of self-compacting concrete (SCC) that eliminates awkward work postures, noise and hand arm vibration, thereby reducing if not eliminating musculoskeletal injuries among concrete workers during their concrete casting work tasks.