Firefighters know some of the most dangerous fires are the ones that should never happen in the first place.

They happen when someone knows the coals in a fire pit should be thoroughly extinguished. They happen when someone knows the smoke detector needs fresh batteries. They happen when someone knows not to walk away from a pot of hot oil on the stove.

They happen because someone understood the responsibility and treated it as less important than it was.

That is what makes the questions surrounding Pittsburgh fire Chief Darryl Jones troubling.

Jones was placed on paid administrative leave last week while the city conducts an internal investigation. Officials have offered little explanation beyond that, leaving the public to wonder what prompted the move involving a chief who has led the bureau for nearly two decades and served under four mayors.

There is much that remains unknown. The investigation may find serious wrongdoing. It may find only administrative deficiencies. It may find nothing that warrants discipline at all.

But the circumstances already feel familiar.

Last year, Jones brushed aside his failure to notify elected officials of his absence during a major weather emergency with a casual, “That’s my bad.”

At the time, there was no indication his absence affected the city’s response to severe storms that downed trees, damaged homes and left one Pittsburgh resident dead. The problem was that Jones failed to follow city code requiring officials to be notified when he was out of town and who would be in charge in his absence.

Now, questions have emerged about financial disclosure forms related to outside teaching and consulting work. Jones has said he performed that work on his own time, and there has been no public allegation that the work itself was improper. Still, records indicate required disclosures may have been incomplete, missing or amended only after questions were raised.

There is no suggestion that Jones acted maliciously. There is no indication that anyone was harmed by his actions or inactions.

What is troubling is the pattern. Whether the issue is notifying elected officials of his absence during a crisis or ensuring required disclosures are properly filed, some responsibilities seem to be treated as less important than they are.

That should concern Pittsburgh residents. Beyond that, it should be a caution to every community. The rules exist for a reason.

The job of a fire chief is not simply responding when things go wrong. It is understanding that small oversights can become big problems long before anyone smells smoke.