August 01, 2018 10:55 AM
The National Transportation Safety Board has issued its preliminary report on the gas explosion that leveled a portion of the building on Minnehaha Academy's upper campus on Aug. 2.
It echoes what NTSB officials said in a press conference the day after: The blast was caused by a gas explosion that occurred as workers were moving gas meters.
The report also details efforts of a maintenance worker at the school who announced gas was in the building and called for an evacuation in the moments before the explosion.
The information in the report is preliminary, and the NTSB states it could either be supplemented or corrected during the course of the investigation.
The explosion killed two school employees - 47-year-old receptionist Ruth Berg and 82-year-old custodian John Carlson.
According to the preliminary report, "two workers were installing new piping to support the relocation of gas meters from the basement of the building to the outside. Two new meters mounted on a wall were ready for the new piping to be connected. While workers were removing the existing pipeline, a full-flow natural gas line at pressure was opened. The workers were unable to mitigate the release of the gas, so they evacuated the area."
The report goes on to say the school maintenance worker heard and smelled the gas and went to the source in the basement meter room. He exited and made an announcement over his hand-held radio, saying there was gas in the building, and everyone should evacuate immediately.
The report states after making that announcement, he raced up the stairs to search for occupants. The building exploded less than a minute later.
The NTSB has said the investigation and full report could take more than a year to be published.
Updated: August 01, 2018 10:55 AM
Created: August 21, 2017 01:32 PM
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