| Name | Age | Sex | Injuries | Injured areas |
|---|---|---|---|---|
| Arnott, Bob | 30 | Male | Burn | Face |
The Blue Grass Grotto placed a register consisting of a large plastic screw-top jar containing paper and pencils in Jingle Hole. A small amount of calcium carbide was placed in the register in an attempt to keep the paper dry.
Dave Kelley (23) and Bob Arnott (about 30), both of South Carolina, rappelled into the pit, and Arnott opened the register. Acetylene gas from the carbide in the register instantly ignited, and Arnott received first-degree burns over the right side of his face. Both cavers left the pit immediately. Medical attention was not required.
The gas seems to have built up in the three months since the last previous trip to the cave. Carbide has been used as a dehumidifier in other cave registers but evidently not enough gas was produced to cause an explosion when ignited. Acetylene gas explosions from carbide have also occurred in Dynamited Cave, Washington, in 1969 and Climax Cave, Georgia, in 1972.
"The value of putting carbide in a register seems questionable. If no gas is produced, then moisture must not have been present inside the register in the first place. If gas is produced, a potentially dangerous situation is set up unless great care is taken in opening the register." (Bishop)