Which of the following is NOT a requirement for firing 7 inch and 8 inch single break shells?

The requirement that the mortar must be metallic is actually not outlined as a specific requirement for firing 7 inch and 8 inch single break shells. NFPA 1123 focuses on safety and effectiveness in the operation of fireworks displays, but it allows for the use of non-metallic mortars, provided they are adequately designed to safely contain the shell during launching.

On the other hand, remote ignition is indeed a requirement for safely firing larger shells. This method minimizes the risk of injury by allowing the operator to be a safe distance from the mortar at the time of ignition. The stipulation that the shell must not be chain-fused is also a significant safety consideration, as chain fusing can lead to multiple shells being ignited simultaneously, posing greater risk of malfunctions and hazards. Mortar racks must be reinforced to ensure they can withstand the forces generated during the launch of these larger shells, ensuring a safe and controlled firing environment. Each of these requirements supports safety and performance, highlighting why the mortar material itself is not specified as a requirement.