How should mortars of various sizes be treated during the performance?

The requirement that mortars of various sizes must not be intermixed is based on safety and performance considerations outlined in NFPA 1123. Each size of mortar is designed to accommodate specific shell sizes and weights. Mixing different sizes can lead to improper launching, which poses a significant hazard, as the threading or fit of a shell may not be compatible with a mortar designed for a different size.

Different sized mortars are engineered to function under certain pressure and projectile guidelines. Intermixing mortars can disrupt these parameters, potentially leading to misfire situations or shells that do not reach their intended trajectory, resulting in dangerous situations for both the operators and the audience.

Furthermore, the separation of mortars based on size helps ensure that all safety protocols are followed, minimizing the risks associated with launching fireworks. Proper handling practices enhance the overall safety of the fireworks display and protect participants and spectators alike.