Dallas, TX – Texas regulators ordered Atmos Energy Corporation to investigate whether couplings linked to an Irving explosion may have been improperly installed all over North Texas, according to state records obtained by NBC 5.

The order, from the Railroad Commission of Texas came after an explosion on Jan. 1, 2018 that destroyed a family’s home. The commission oversees pipeline safety.

Atmos crews were fixing a natural gas leak in an underground pipeline when a house just yards away exploded and caught fire.

“It sounded like a bomb,” a neighbor said at the time. “It shook the house.”

The family of five inside somehow made it out unhurt. They said they were frustrated that hours earlier, an Atmos worker had told them there was no need to evacuate.

“He said, ‘If you’re fine, then we’re fine. Everything is fine,’” Alejandra de la Cruz said.

The house was destroyed.

But what caused the explosion?

A month later, in an initial report to the Railroad Commission, Atmos denied the blast was even related to natural gas.

“Did the gas ignite? No,” Atmos answered on an official form. “Did the gas explode? No.”

In later reports, Atmos changed its answer, admitting it was a gas explosion, and blaming it on an improperly-installed coupling which connected two six-inch pipes.

The commission fined Atmos $16,000 and cited the company for three violations of minimum safety regulations:

Atmos didn’t take prompt action to eliminate hazardous conditions and make repairs.

The pipeline was not designed and/or properly installed.

Records were not maintained or were inadequate.

The commission ordered the company to correct the issues and submit a correction plan.

In October, the state rejected key parts of Atmos’ plan, and said, “(Atmos) must investigate if this situation exists elsewhere.”

A month later, Atmos wrote back: “Atmos Energy is reviewing our current processes and procedures … to prevent a similar event from occurring. This review will be completed by June 30, 2019.”

The commission told the company to finish by May 7.

The order is notable because the commission has been criticized for being lax in its enforcement.

Brigham McCown, a former pipeline safety expert for the federal government, said the $16,000 fine isn’t enough to get the attention of a large company like Atmos.

But he supported the state’s push to get Atmos to come up with a corrective plan.

“I do think that’s encouraging,” McCown said. “At least the Railroad Commission now is saying, ‘Hey you need to go out, we’ve identified a problem and now you need to take a holistic approach to determine whether or not you have other issues where similar occurrences happen.'”

It’s not clear how many of the couplings exist or what Atmos will do to check their safety.

In an August letter to the commission, Atmos vice president for technical services Jeffrey Knights said the utility “makes no admission” that it violated any safety rules and said its procedures comply with government requirements.

Atmos spokeswoman Celina Cardenas declined to respond to detailed questions from NBC 5 about the case.

In an email, she did offer a generic lesson of how the regulatory process works.

“The RRC’s enforcement action policy is to improve safety and promote compliance,” she said. “This case settled.”

She did not mention the commission’s order to investigate the couplings or the May deadline. The records reviewed by NBC 5 show the matter is still not settled.

The month after the Irving incident, another explosion in Dallas killed a 12-year-old girl and forced a long evacuation of the neighborhood while Atmos repaired lines.

The investigation into the Dallas case is being led by the National Transportation Safety Board, which still hasn’t issued its report.

An NTSB spokesman said on Monday that the agency’s investigations typically take one to two years.