On August 2, 2017, at 10:22 a.m., local time, a building on the north campus of the Minnehaha Academy, a private school in Minneapolis, Minnesota, was destroyed by a natural gas explosion. At the time of the explosion, two workers were installing piping to support the relocation of gas meters from the basement of the building to the outside. Two new meters mounted on an exterior wall were ready for the piping to be connected. While workers were removing the existing piping, a full-flow natural gas line at pressure was opened. The workers were unable to control the release of the gas; thus, they evacuated the building and warned others to evacuate. The explosion occurred during their evacuation. Two individuals were killed, and nine others were injured.
We determined that the probable cause of the natural gas explosion at the Minnehaha Academy was the disassembling of piping upstream of a gas service meter in the building by a pipefitting crew, resulting in the release of natural gas, which subsequently ignited. Contributing to the accident was the lack of detailed documentation that clearly established the scope of work to be performed.
