[lightman]

In my part of southern PA at least one house is leveled every winter due to NG explosions brought on by deep freeze cracking of the lines.

Happened to a small town fire chief about 20 years ago.

We hate the digging up of the streets for line replacement but those old pipes are killers.

[fireman15]

For some reason houses blowing up is not a common occurrence where we live. I suppose it is because the weather is more mild and the infrastructure is newer.

We went to a major gas leak one evening. A main in the middle of a road that was being upgraded was hit by an excavator. It was very noisy and the surrounding area did have the associated stench. Because of the size of the main the gas company couldn't turn it off without causing a major disruption in service to thousands of homes. Fortunately it was in an industrial area, after hours with only one home nearby. They were unhappy that we made them evacuate.

We were the first units on-scene I was the senior officer in charge of the hazmat team. But the gas company's emergency response team was notified first and arrived before we did. I asked them what they needed us to assist them with.
They just wanted us to cover the team that was going into the trench with hand-lines in case the gas somehow caught on fire.

I asked them what we should expect if the gas did ignite. I was told it would create a big fireball that could be dangerous especially to anyone who wasn't wearing protective gear and then a giant torch that would create enough heat to be dangerous to personnel and equipment nearby. They felt that because of the conditions that it was not an extremely dangerous situation.

When my battalion chief came by to check on us an hour or so into the event, he and his aide became highly agitated and thought that this could result in a huge explosion that would flatten surrounding structures and kill a bunch of us. I told him that the gas company technicians didn't think so. He remained skeptical and I have heard of events that have resulted in major damage and casualties. But it depends on the wind conditions, the terrain, the temperature, the buoyancy of the gas and other factors. I trusted the judgment of the gas company emergency response team leadership.