Safety snap-hooks are a critical component of a fall-arrest system worn by individuals working at elevated heights. Current snap-hook technology has not evolved in many years, and as a result, the hooks are both heavy and conduct electricity. This project investigated the design and manufacture of a polymer-composite safety-snap-hook. The objective was to determine whether a light-weight, dielectric, composite hook can meet the safety requirements, while being manufactured at a competitive price. Several fibre arrangements were tested using current aluminium hook geometry. A research plan was designed and completed to maximize the hook strength by optimizing fibre architecture. These results were then used to design a composite hook that meets all the current CSA standards (static load, dynamic load, side and front load gate test). The design enables the hook to be completely non-conductive and lighter than the current pincer hook. Different manufacturing techniques were also considered and it was determined that both the net-shaped moulding and vacuum bag panel method were suitable techniques. It is recommended that further research be carried out to decrease the cost of the composite hook. Less expensive resin materials should be tested to determine how much strength is lost with lower grade resins. A standard test should also be developed so that hooks can be characterized for their electrical conductivity. In addition, research is required to find a process to cut the mats so that the cut-outs can be handled without falling apart, making the net-shape moulding process more suitable. Further design modifications are also needed to meet newly proposed gate regulatory standards. Research is required to determine whether increasing the thickness of the gate or embedding a metal reinforcement would provide the required gate strengths. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2007-09-25 13:25:27.368