Orb of Clear Air (3.5e Equipment)

Orb of Clear Air
This device appears as a basketball sized crystal ball which is filled with a rolling white mist that seems to originate from its apparently hollow center. The sphere gives off a pale blue light when active.

The orb of clear air is afixed in a vehicle or structure and constantly refreshes and recycles air in a given sphere (default 60 ft radius). It also warms or cools the air to comfortable temperatures over time, so unusually hot or cold air coming in still needs at least 10 minutes to reach normal temperatures. At the edge of the sphere is a thin force field, strong enough to keep in (or out) gases and small particles like dust and tiny grains of sand (even those moving at high speed), but provides no resistance to larger or denser materials like water, rocks, or people entering and leaving. Wind passing through the force field drops to no stronger than moderate, though high winds produced inside the sphere act normal. It is often used on spacecraft to provide an atmosphere to an otherwise non-airtight ship.

Because it is strong enough to stop gases, the shield is sometimes visible as an empty space in a field of fog and wind.

Orbs with larger and smaller radii exist. The formula for the price of a different radius the number of 10 ft radius (in this case, 6) squared x 50 + 1000. Minimum 10 ft.

Moderate transmutation; CL 6th; Craft Wondrous Item, tiny hut; Price Cost::2,800 gp.