In accordance with the ceremonial standard operating procedure (SOP) of the 3rd U.S. Infantry (The Old Guard) the various gun salutes are assigned as follows: each round in a given salute is fired one at a time. The number of cannon used in a battery depends upon the intervals between each round fired. This includes, for example, a three-gun battery firing two of its guns with five-second intervals between rounds and one gun remaining at the ready in case of a misfire; such a battery would be used at an Armed Forces Full Honors Funeral, or for State Arrival Ceremony of a foreign dignitary at the Tomb of the Unknowns in Arlington National Cemetery. A four-gun battery has its first three guns firing rounds at three-second intervals, with the fourth gun (again) at the ready in case of misfire.