In the incredible Deadpool movie, we get to see how Wade Wilson becomes Deadpool. For the final stage of his transformation, he is fastened into a glass/metal chamber by his neck, arms, and I assume legs as well. Once he mutates, he attempts to escape the chamber by igniting the oxygen supply (which btw, doesn't work because oxygen is not a fuel, it is only an oxidizer, but I won't get into that). He successfully leaves the chamber, before losing a fight and remaining to burn with the entire facility.
I am wondering how he ever escaped the chamber? The glass seemed pretty thick and he was fastened in pretty well. I thought well maybe he broke out, but that's probably not true, because those chambers were designed to hold even stronger mutants like Angel Dust. Plus, if he was strong enough to break out, why cause the fire in the first place? Just break out and breach the part of the lab where Francis is.
Then I thought maybe some debris broke his chamber and he escaped. However, this is also unlikely because the debris would not just randomly break through and cut his straps without taking pieces of his body (he seemed to be whole when he got out, and his regen isn't very fast). Also, if debris could break it then other mutants should have been able to get out and it's likely they would have attacked Francis.