A mailslot or other file system containing a notecard with a planned response to an incident type. For example, a reported structure fire on Some Road would be tagged with Box 6; the notecard in Box 6 would contain the list of apparatus from various fire stations that should be dispatched to that incident. Assigning Boxes to areas (or even specific structures) significantly facilitated the process of getting the right tools to the right place on the initial dispatch, and helped eliminate the guesswork of "which department has what" on the fire scene. Boxes later evolved to contain escalation procedures - on the "2nd alarm", the Box would contain the next group of apparatus from various fire stations, etc. Modern CAD systems now abstract the Box Alarm concept, and allow box definitions to be triggered based on arbitrary geographic area, time of day, incident type, weather, and any other planned situation. For a given hydranted area, the "Summer" box will contain the usual response of engine, truck, and rescue companies. In the winter, however, the box may be modified (automatically, or manually) to include water tankers on the initial dispatch, to handle the case of frozen hydrants. The term "Box" comes from the fire alarm pull boxes that were commonplace in major cities for well over fifty years. This was a telegraph system that involved bells to ring out the box number. This system was in place from the 1920s (or earlier) to well into the 1960s and 1970s in some cities. Boston was one of the first (if not THE first) major U.S. Cities to have a telegraph alarm system. They installed it in 1852. The Boston Fire Department still uses this system of paper rolls and bells. The modern use of "box cards" based upon an imaginary box location for dispatch or move up is often known as the "Phantom Box System".

Also, an antiquated term for an alarm system which predated telephones, where boxes were located on street corners in urban areas and connected to the nearest fire station.