Vacuum Seal

The spell creates a magical airtight seal. The area appears as a translucent blue barrier. Solid and liquid objects can still pass through the seal, but gasses cannot. The area can take whatever shape the caster desires. If the area is adjacent to, or overlaps another instance of this spell, the edges can be joined. If this spell is cast over a wall or physical boundary (i.e. over the hull of a ship, or on the walls of a room) The duration becomes 1 week.