Everyone knows what can happen when a can of shaken soda is opened. But when that can is opened in a highly pressured environment, like a habitation unit at the bottom of the ocean, things are a little different.
Astronaut Chris Hadfield is in a vessel this is pressurized to two and half atmospheres. He shows that a can of Coke, after being shaken up, will not erupt if you open it in a high pressure environment. When you shake a can of soda, the internal pressure increases greatly. The difference in pressure between the inside of the can and the outside (on the surface of the Earth) causes an explosion. If the outside pressure is equally high or higher, there is no pressure difference and therefore no explosion.