A team of coal miners is working hundreds of feet underground when an explosion rocks the tunnel. They scramble for an exit, but those are all blocked. The air fills with dust and gas. There's no escape ... so the survivors inflate a portable panic room, complete with an oxygen supply and air filters, and wait for help. At least that's how Jim Reuther, a senior research scientist at the R&D giant Battelle, hopes the situation pans out.