Unlimited Oxygen and Build Indoor Items Outside Glitch | Build 33409 May-2016

I found a way to exploit the game to have unlimited oxygen, allows you to build indoor items outside, and prevents monsters from attacking you. The game will treat it as though you are inside even though you are outside (this means no swimming, you can only walk the bottom of the ocean floor).

I'm not sure how easy it is for someone else to duplicate, but here is my setup:
1x moon pool
1x foundation
1x multi-purpose room

(You may be able to use a room other than the moon pool, but this is what I was using when I discovered this trick).

Replicating conditions:
Build foundation; build-multipurpose room; build moon pool with a slight gap away from the foundation. The moon pool and multi-purpose room will auto-connect.

This is what it should look like:



Notice the outdoor fabricator.

To activate the glitch, be inside and walk over the corridor. When you cross the part not supported through the foundation, you will fall through the base onto the ocean floor. At this point, the game will treat you as though you are still inside. You can fix this by approaching the hatch from the outside and "exiting".