I've come up with an idea for Dai's costume, here it is

Main body:

The main jumpsuit is made from a waterproof fiber that allows the flow of anything in it and the shoulder armour allows for the canisters of biological substances to be attached.

Helmet:

The helmet visor armour can open and close to allow another source of visual info if the cameras on the armour were broken or malfunctioning. The light on it can be used in dark situations for more accurate data collection. The respirator is equipped with state of the art filtering systems for any situation whether underwater or not.

Vest and back:

The vest can be used to carry his support gear and other supplies such as biomass and medical material. The back (look at right) can be used to carry other supplies like rope, water, food etc in rescue situations. (Dai has good back strength)

Support gear:

The stun baton is a useful tool in his arsenal, it's... A stun baton what do you expect? It's also a flashlight.

He may have some concussion grenades but that's for later.

There might even be a rifle hidden in his home for goodness sake because as a wise man once said "if something doesn't die when you shoot it, you probably didn't shoot it enough"

Canisters:

Can't find an image but imagine the canisters like about the size of your forearm and they have a meter of how much is left.

Medical stuff for Dai:

Stimulants. Improve fatigue and concentration. These drugs include methylphenidate (Ritalin, Concerta).

A/N: yes the suit was inspired by trauma team from cyberpunk and also I don't exactly know how to draw the whole thing together so I guess it'll be fine.