The Decompression Windows are a new feature in Dead Space 2. They are large windows that you can shoot in order to cause a vacuum that will suck anything in the area out into space including Isaac. Shooting one will trigger a sequence where all Necromorphs in the area are sucked out into space and Isaac slid across the floor toward the window. The player had to shoot a red switch at the top of the window in order to close it. If Isaac did not shoot the switch, it is an instantaneous death.
- Is recommended that you stay far away from the windows if you plan to shoot it as you will not get enough time to shoot the switch if you stand too close.
- Decompression Windows had a limited range. This can be easily seen in Chapter 7. There is one room that had a Decompression Window. If you stand far enough to the side when you shoot it, you will remain unaffected while everything else is sucked out.
- Also, the windows only affected the room that it is in. In Chapter 4, the only Decompression Window is opposite the door to the hall. If you stand in the hall, but close enough to the room to keep the door open and you shoot the window out, the room will decompress, but you, in the hall will not move. The window will close after some time and you do not have to shoot it to close it. However, if you enter the room while it is decompressing, the sequence will initiate and you can still get killed.
- There are two Achievement/Trophies involving Decompression Windows. "Skewered in Space" requires you to impale a Necromorph to a Decompression Window, causing it to break. The other one, "Vacuum Cleaner" requires you to kill twenty Necromorphs using Decompression Windows without getting sucked out yourself.
- A strange thing occurred after Isaac's battle with The Tormenter. When he crashed through the window, all of the oxygen is sucked out, but none of the candles on the floor are affected and none of the lights are extinguished.
- It is extremely strange how the Window's emergency shield rose ONLY when Isaac is in position to be killed by it. If this is a feature to prevent multiple people being decompressed, it did not explain why the shield did not rise after a Necromorph passed through.
Should Isaac fail to close the window in time, one of the following death scenes will occur:
- Isaac will attempt to get away, but the window's emergency shield will rise, pinning him to the ceiling. It will continue pressing against Isaac's torso until he is split in half.
- Same as above, except the shield will be pressing against Isaac's back until he is split in half.
- Isaac managed to stand up right next to the window. However, the shield rose, catching both of his arms in between the shield and the ceiling. His arms are severed and Isaac fell to the ground. He died from his injuries.
- Isaac got pinned by the shield at his torso, but the force of the vacuum still sucked him out. As he continued to slide through, his arm got caught. It got severed and Isaac flew out into space while his arm fell onto the floor.
- When you have to close your first Decompression Window in the beginning of the game, should you fail to do that, Isaac will be sucked toward it, but cringed to a table. The force of the vacuum is enough to sever Isaac from his arm. He flew toward the window and bashed his head against the wall before getting sucked out into space.
- There is an unused death scene in which Isaac will attempt to kick away from the door while on his back, but both of his legs will get caught in the door. Isaac will attempt to pull them out, only for them to get severed, leaving him to attempt to crawl away, then bleed out shortly after. This is seen in the Dead Space Gameplay Reel video currently up on YouTube at the 0:23 mark.