What is the maximum interval allowed between reinforcements or braces for mortar racks?

The correct maximum interval allowed between reinforcements or braces for mortar racks is 4 feet. This requirement is specified in the NFPA 1123 code to ensure the structural integrity and stability of mortar racks during fireworks displays. Proper bracing and reinforcement are critical for maintaining the position and security of the mortars, which helps prevent accidents and enhances safety during the display. When mortar racks are adequately supported, they can withstand the forces generated by the launching of fireworks, thereby reducing the risk of tipping or collapse that could lead to hazardous conditions. Ensuring that the bracing is not more than 4 feet apart is a key safety measure mandated by the standard.