Builders liability insurance holders have been told that it is vital that they understand the risks of working in the industry.
Paul Harvey, Health and Safety Executive principal inspector for construction, said that working on building sites is one of the most dangerous jobs, with many potentially lethal hazards.
He added that working at height, asbestos and site transport all create risks, and it is important for employers to understand this so that they can manage hazards effectively.
Huw Llywelyn, chairman of the South Wales Working Well Together partnership, commented: "Working Well Together is about highlighting how effective planning can prevent deaths and injuries on sites and the mock trial will demonstrate the legal responsibilities that site managers have.
The Working Well Together website gives builders liability insurance holders important information about how they can prevent accidents in the workplace by involving their staff in safety planning.