A Warning line system helps create a clear visual boundary around hazardous areas, especially on low-slope roofs where workers may be exposed to fall risks. It helps alert employees to stay within designated safe work zones and supports a more organized approach to workplace safety. Proper placement, visibility, and regular inspection are important for maintaining an effective system. When combined with suitable fall protection measures and proper worker training, warning lines can help reduce unnecessary exposure to roof-edge hazards and improve overall job-site safety.