Minimum standards for use of single-break aerial salute shells shall include :
1. nonmetal mortars
2. individual mortars more than 3 in. in diameter and length shall be individually supported and separated from other loaded mortars by at least 10 times the inside diameter of the largest mortar
3. individual salutes more than 3 in in diameter and length shall be permitted to be fired from racks, provided that only one mortar in the rack is used or unless the distance between loaded mortars in the rack meets the requirements of (2) above
4. remote ignition or use of an added 5 second minimum time delay fuse extension shall be used
5. salute shells shall be preloaded into mortars