Trifold Elemental Barrier

You create a 10ft sphere of shimmering force centered on a space you can see within 100 ft.

When you cast this spell you can choose Fire, Water, Earth, or Air.

Beings or energy with any of the other elemental types may not pass through the Trifold Elemental Barrier.

The Trifold Elemental Barrier is frequently used by alchemists to isolate the elements in an arcane experiments. 

When you cast this spell, you can cause it’s magic to work in reverse, preventing the specified energy from escaping.

At Higher Levels. When you cast this spell using a spell slot of 8th level or higher, the radius increases by 10 ft.