Saturation Diving 200m Guide: Trimix, MK-II & Ascent

What gear do you need for 200m in Saturation Diving?

At 200m you are in the Trench. Use Trimix with a Pressure Suit MK-II, carry a 35% oxygen reserve, and treat the route as a darkness-and-pressure operation rather than a longer Continental Shelf run. The suit protects against barotrauma and depth-shift crushing damage through the 200m threshold.

200m route check	Standard
Depth zone	The Trench (120–250m)
Gas	Trimix — 10% O₂, 70% He, 20% N₂
Suit	Pressure Suit MK-II
Oxygen reserve	35%
Main hazards	Total darkness; Leviathan acoustic aggro
Main resources	Abyssal Crystals; Uranium

How do you navigate the 200m Trench?

Use short pulse-sonar pings and keep the crew on a known tether or landmark line. Floodlights draw attention in the hadal zone: high-beam light expands predator detection from 15m to 65m, so a bright beam should never become the default navigation method.

The Spotter calls the next safe line, the Captain decides whether to advance or turn, and the Engineer stays ready for recovery. The Salvager only starts an extraction when the 35% return margin remains protected.

How do you return safely from 200m?

Use the SD-W 45/10 Ascent Rule exactly: climb at no more than 0.5m/s, hold 45 seconds at 30m, then hold 45 seconds at 10m. If The Bends triggers, move into the Hyperbaric Chamber within 30 seconds, set the pressurisation valve to the deepest dive level, and wait 60 seconds for the toxicity meter to clear.

Avoid repairing the Diving Bell from the exterior below 150m. Use the Decompression & Gas Calculator before launch and the Deep Diving Guide for the full hazard and upgrade order.