What must be done if salute shells are to be fired from racks?

When firing salute shells from racks, it is essential to ensure that only one mortar is used in each rack. This is primarily to maintain safety and manage the specific hazards associated with salute shells, which are known for their loud sound effects and explosive nature. If multiple mortars were permitted in a rack for salute shells, it could lead to a dangerous chain reaction in the event of a misfire or malfunction, significantly increasing the risk of injury or property damage.

Limiting the operation to one mortar per rack provides clear control over the firing process and minimizes the potential for overlapping effects that could lead to confusion or hazardous outcomes. This practice aligns with the NFPA 1123 standards which emphasize safety measures specifically tailored for the handling and display of fireworks, especially those with high explosive capabilities like salute shells.