system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why don’t structure fires create a chain reaction of gas line explosions the lead back all the way back to the source?

Edit:  sounds like the consensus is lack of oxygen in the pipe network and one way valves. Thanks folks!
gpt
You can't have an explosion without oxygen. Gas pipes are full solely of gas, and they're also really quite tough. You have oxygen at the end of the pipe, so you might get a fire at the end, but the oxygen won't burrow down into the pipe because the hot gasses (CO2 and water) that are bursting out of the end of the pipe don't let anything else come back the other way. As a result, gas pipes tend to just keep a small flame at the end of them during a fire, rather than having the fire chase down the entire pipe.