so a house in my neighborhood blew up...

[DrPizza]

Last friday utilities company came around . Our area lost gas . So he refired the hotwater heater. I told him I was thinking of upgrading the hot water heater , He told me not to , It seems that some of the newer stuff can explode when you loose gas and on restart Ka-Boom

Ummm, are you freaking kidding me??

 

[FirNaTine]

I work for a NG company, so I speak from experience.

4% - 18% gas to air ratio for NG to burn or "blow up".

Also, there is this thing called migration. There are many instances where lines have been nicked or small punctures happen, even without the contractor knowing about it. Depending on the soil type or rock formations in the soil, gas can migrate for pretty good distances before it escapes the ground. Unfortunately, sometimes this is a basement wall.

Most home explosions are due to migration, whether it be from a line hit or just old and degraded leaking pipe.

To expand/clarify on what he said: When you dig to lay a gas line you create a pathway of lower resistance in the soil for the gas to follow when it escapes the pipe. It can follow the disturbed earth to the foundation of a building and infiltrate it that way.

Realize also that a lot of new utility work is done with directional drilling, not giving a direct path to the air. Even if it is open excavation, a backhoe or similar excavator isn't particularly sharp. It may hook the line, and pull a remote joint (say close to the foundation) apart instead of breaking it directly at the point of contact.

Let's just say I spent most of my day dealing with this yesterday, but luckily it did not ignite inside (only outside). The utility was able to control the leak eventually, and we were able to clear the building of gas afterwards. The article on it is not even close to accurate, so I won't bother linking it.

This is a known phenomenon, and something we have learned from prior tragedies.

 

[PieIsAwesome]

Good to see the neighbors being concerned and helping. If this were in china, the neighbors would probably just run over the burning people with their cars and then loot the corpses.