A huge mod obviously

See this other Steam Guide for the big picture:
https://steamproxy.net/sharedfiles/filedetails/?id=3020052016

Coding
- Exposed player receives minor damage-over-time below 100m
- Damage rate increases with depth (exact rate TBD)
- 900m soft barrier for divers (damage becomes unmanageable)

Suggest starting out with something like this, then tweaking a set variable

Variables:
AmbiDamage (Ambient Damage depletes health each second)
setDamageVariable = 1

if depth > 99m
then AmbiDamage = (depth/100)* setDamageVariable

Coding
- Standard wall and ceiling hatches trigger the base flooding animation
- All standard hatches inoperable below 100m

- modelling (simple)
- coding functionality
(see link below for details)

- modelling (simple)
- coding functionality

- modelling (complex)
- coding functionality

- flooding
- draining
- on-board scuba regulator

- Hatch made inoperable whilst submerged
- Remains still afloat immediately after construction for first time entry

Couple of options:
- Several module 'tool arms' (Builder, Scanner, Cutter)
- Animate existing Prawn arm Claw to use any tool from player's inventory (PDA could merely comment that the Prawn features a 'Tool Airlock' that allows this).

- coding functionality

- Obtain permission / participation from existing mod creator?
(see link below for details)

Cyclops Docking Tube (an existing mod):
https://www.nexusmods.com/subnautica/mods/554

Wet Airlock (detailed notes for modellers and coders - PM me for this)
https://steamproxy.net/sharedfiles/filedetails/?id=3023447963&preview=true