Clues to Ballantyne 'interior gas' explosion are in debris, experts say

Fire investigators announced an "interior gas leak" as the most likely cause of Tuesday's deadly home explosion in Ballantyne. Experts say the clues are in the debris.

"It was absolutely gas related," a fire investigation expert, not connected to the case, told FOX 46 after reviewing images and video from the scene.

If this had been caused by gasoline or explosives, there would have a bigger fire and a crater left behind, experts said. The absence of both suggests a natural gas related explosion, which investigators announced as the preliminary cause late Wednesday.

Charlotte Fire releases preliminary cause of Ballantyne home explosion

"We have identified the most likely cause as an interior gas leak," the fire marshal said. "We still have some work to do so the investigation is ongoing."

Since the home has been reduced to rubble, the extent of the damage will make it difficult for investigators to determine the ignition source, experts say. Investigators will likely keep zeroing in on the home's gas system looking for open valves or broken lines.

Natural gas is odorless which is why odorants are added to detect leaks. Experts say the level of gas needed to create an explosion (5-15 percent natural gas to air) should have been detected.

"Somebody should have smelled it," an expert said. 

Investigators will likely take samples of gas, reconstruct the gas system for the home and analyze the victims' injuries in order to better understand what happened.

Police: Survivor in Ballantyne house explosion 'has no idea what happened'

Piedmont Natural Gas services the area and says no natural gas leaks were detected.

"Yesterday, our technicians tested and checked the Piedmont natural gas lines in the area," said spokeswoman Jennifer Sharpe, "and no natural gas leaks on our lines were detected.​​​​ We've determined the Piedmont natural gas pipelines in this area are operating safely."

"We are deeply saddened by the tragic loss of life," Sharpe said. "Our condolences and prayers are with those who are injured and who've lost a loved one."

Fire officials have not ruled out whether the home ever had a private gas line installed, which would be the responsibility of the homeowner and used for things such as a grill station or a fire pit. FOX 46 checked permit records for the past six years but found none.

The feds are now looking into all of this. The Charlotte Bureau of Alcohol, Tobacco, Firearms and Explosives confirms it sent its fire investigators to the scene, as requested, to figure out where the fire started and why.