BOISE, Idaho — A propane leak that led to flammable gas slowly pooling in the crawl space beneath a McCall home is to blame for the massive explosion that killed a man and badly injured a teenage girl.
Idaho State Fire Marshal Knute Sandahl released the result of the investigation Wednesday, while urging all Idahoans to guard themselves and their houses from a similar tragedy.
The March 17 explosion completely leveled the house on Fairway Drive, near the McCall Golf Club. The force of the explosion drove boards through the roofs of nearby homes and left a field of smoking debris where the home had stood.
Jonathan Robinson Field Jr., the 69-year-old owner of the home, was killed instantly. A 15-year-old girl survived, pulled from the shoulder-deep rubble by two firefighters who heard her screaming for help.
"That person, that survivor, owes her life to two very brave and courageous firefighters," Sandahl said. "Those firefighters, John Metz and firefighter Jason Beck were running errands on that particular day, heard and saw the explosion and responded to the scene."
The pair pulled on their protective clothing and waded into the debris field armed only with a pressurized fire extinguisher to save the teen. She was airlifted to Saint Alphonsus Regional Medical Center for treatment.
"Their actions, in my opinion, are the reason this young lady was able to survive this horrific event," Sandahl said.
Although the 15-year-old remains hospitalized, she is making "a miraculous recovery," he added.
Because the cause of the explosion was at first unknown, the Bureau of Alcohol, Tobacco, Firearms and Explosives was called in to help. Ultimately, investigators were able to determine that a flammable gas - propane - was the culprit, rather than a bomb or other type of explosive device.
McCall home explosion kills one, injures another
The girl who survived told investigators she had smelled propane in the house the day before the explosion. Propane manufacturers intentionally add in an unpleasant odor - similar to skunk or rotten eggs - to help people detect a propane leak.
The girl told her guardian about the smell, but he didn't take it seriously, Sandahl said.
"Unfortunately, this smell was disregarded as the smell of dirty laundry," he said.
The McCall area had received a massive amount of snow in February, but by March, temperatures were rising, hitting the mid-40's in the days leading up to the explosion. The warming weather resulted in a number of snow slides, with melting piles of snow slipping off of roofs.
That snow put additional weight on the home's propane meter and regulator, causing a fracture inside the wall of the home, investigators found. Propane leaked out, pooling in the crawl space beneath the home. As it built up, Sandahl said the flammable gas began leaching up into the first floor of the house, where the residents kept the furnace.
"We believe that the furnace was the ignition source," Sandahl said.
Sandahl urged residents who rely on propane or natural gas to protect themselves, especially during the winter months.
"When a snow slide occurs, clear it out right away," he said. "Create a path to your regulator. Create a path to your meter. Clear off any snow that has built up on the propane tank."
When clearing snow from a roof, a simple piece of plywood can be used as a temporary shield to make sure the heavy snow is not plummeting onto a propane line.
Purchasing and installing a flammable gas detector can also provide an early warning if a leak does occur, Sandahl added.
"This is a relatively inexpensive cheap insurance that can essentially save your life," he said. "If you smell [gas] or one of these detectors does activate, I urge everyone to immediately evacuate and call 911."