Which type of shells cannot be fired from mortar racks?

The rationale for selecting the type of shells that cannot be fired from mortar racks lies in the safety and operational limitations outlined in the NFPA 1123 guidelines.

Single break shells greater than 8 inches and multiple break shells are designated as larger and more complex types of aerial shells that require specialized firing setups. Mortar racks are typically designed to safely launch smaller single break shells, which have a simpler design and lower safety risk compared to their larger counterparts. The increased size and complexity of these larger shells present greater hazards not only in terms of the physical force generated during launch but also in the potential for malfunction, which could endanger spectators and personnel if attempted from standard mortar racks.

Additionally, the necessity for precise launching angles and distances when deploying larger shells aligns with the recommended practices in NFPA 1123, ensuring a higher degree of separation from spectators and structures. These shells must often be fired from more robust platforms or custom-designed systems to ensure safety and effectiveness.

Understanding this distinction is crucial for planning safe fireworks displays and mitigating risks associated with firing different types of aerial shells.