The purpose of this study was to increase the safety of explosive storage. A recent increase in magazine explosion frequency must be attributed to an increase in deliberate (criminal or malicious mischief) explosions. Fires of various origins account for the remaining explosions of the past decade. During 1884-1926, several lightning-generated explosions occurred in nonmetal magazines, but it appears that a well-constructed metal magazine is immune to direct lightning strikes, regardless of whether it is grounded or not grounded. Grounding a metal magazine cannot be harmful, but it may well be superfluous. Magazines were observed at 34 widely separated mines, and storage problems were discussed with personnel at those mines. In general, storage conditions and practices were found to be satisfactory. Standards on explosive storage appear to cover safety aspects adequately; however, certain revisions are recommended to clarify.