The Indiana State Fairgrounds Coliseum gas explosion took place in Indianapolis, Indiana, United States, on October 31, 1963; 81 people died and about 400 others were injured. It was one of the worst disasters in the history of the state.
On the night of October 31, over 4,000 people were in the Indiana State Fairgrounds Coliseum to watch a Holiday on Ice performance. While this was happening, liquefied petroleum gas was leaking from a tank that was stored with several others in a supply room underneath a part of the grandstands. Shortly after 11 p.m. ET, the gas came into contact with an electrical heating element from the concessions area, causing a major explosion that killed many seated above the room and caused significant damage to the stands. After the initial blast, while people were evacuating, a second blast caused by the remaining, unexploded tanks caused further destruction. Firefighters and other emergency responders were at the site within minutes and survivors were transported via ambulance to various hospitals in the area. The gas tanks were discovered by firefighters during cleanup operations and later testing revealed that they were the cause of the explosion.
Following the disaster, a grand jury indicted seven people in total, including employees of the gas provider and the company that operated the arena, as well as the state fire marshal and the city fire chief. However, at later dates all of the individuals either had their charges dropped or their convictions overturned. Victims of the explosion were eventually awarded $4.6 million in settlements. Several city and state agencies investigated the explosion, and it was one of the first events studied by the Disaster Research Center, a research group organized earlier that year to study large-scale disasters. The arena reopened about six weeks after the incident and still stands on the Indiana State Fairgrounds.
Background
The Indiana State Fairgrounds Coliseum is a multi-use arena with a seating capacity of about 7,800 located on the Indiana State Fairgrounds in Indianapolis. On the night of October 31, 1963, 4,327 spectators were present at the arena to see the opening-night performance of Holiday on Ice. This was the first performance of the ice show's scheduled eleven-day run in Indianapolis, and the coliseum promoted it as part of its "Shriners Night". It had been raining throughout the night and, because it was Halloween, the Indianapolis Police Department (IPD) had activated more police officers than usual. The show had been scheduled to begin at 8:30 p.m. EST, but it had started about fifteen minutes behind schedule, and around 11 p.m., the finale was about to begin.
Explosion
The explosion occurred at 11:06 p.m., during the show's finale. The explosion was centered on the southeastern end of the arena, just underneath the box seats of Aisle 13. The initial blast lifted approximately of floor and launched debris and spectators towards the ice rink. Shortly thereafter, a load-bearing wall underneath the stands gave way and caused an additional cave-in of about of floor. A few minutes after the initial blast, a smaller explosion occurred that produced a fireball that rose high. Both before and after this second blast, evacuations of the arena were underway, with the spectators mostly leaving in an orderly fashion. During the evacuation, the Holiday on Ice orchestra continued to play and reports of the evacuation make note that there was no significant mass panic, with many of the evacuees experiencing shock. The location of the explosions had left a crater measuring approximately across that contained a great deal of rubble and a small fire.