As the title says, Biolabs will not push oxygen into adjacent pipes like they do with petroleum gas and greenhouses do with water.
Biolabs will still push oxygen into directly connected biolabs, but if there is any pipe in between the oxygen will not transfer.

I have tested with both regular and steel pipes in both directions. Pet gas passes through just fine.

Tested on version 1.0.7 and 1.0.4

Work as expected:

Tested on (1.0.7)
Pipes are not granted, in that case u should use an external pipe or pump, thank game developers for the limitation.

I know that it works when the bio labs are adjacents, but the inconsistency lies in pipes.

Petroleum gas (bio lab) and water (greenhouse) are pushed through to pipes, but oxygen is not.

In the picture, you can see that the right pipe is not filled with oxygen, but the top pipe is filled with petroleum gas. Also see how water passes through the greenhouses in the bottom left. As a workaround I could use pumps as those do pass through oxygen properly.

Sorry to bring up this thread again, but I am still curious about the differing behaviours.

I am absolutely loving the mod btw