Donarun Das
Engineer-Diver. From first breath to 100m.
TDI Trimix · Sidewinder CCR · PADI Staff Instructor
15+
Years Diving
TDI
Trimix Instructor
PADI
Staff Instructor
Sidewinder
CCR Instructor
E-Learning Platform
Continue your training online.
Self-paced theory, videos & quizzes for every course.
Same account online or in person.
Meet Donarun
A mechanical engineer who teaches diving — from first breath to 100m.
Donarun Das is a TDI Trimix and KISS Sidewinder CCR instructor based in India, also certified as a PADI Staff Instructor. A mechanical engineer from NIT Silchar turned full-time diving professional, he brings 15+ years in the water and a stubbornly analytical approach to teaching divers across the full spectrum — first-time recreational students through advanced rebreather and trimix.
Most courses he teaches are run privately — usually 1:1 or 1:2 — and built on physics, physiology, and methodical skill repetition rather than checklists. He leads expedition projects in Lakshadweep's deep walls and the cave systems of Meghalaya, and writes about decompression theory, gas planning, and the failure modes nobody wants to teach.
A quick career sketch
-
2010
Engineering, NIT Silchar
Mechanical engineering; later R&D at BHEL on CFD and turbine systems.
-
2011
First certification
Open Water with SSI. The start of 15+ years in the water.
-
2016
Instructor qualifications
PADI instructor — and then progression towards IDC Staff Instructor.
-
2023
CCR & Trimix specialist
TDI Trimix and KISS Sidewinder CCR instructor — for deep, decompression, and expedition diving.
-
Ongoing
Exploration projects
Meghalaya cave systems, Lakshadweep deep walls, across Maldives.
Teaching credentials
- TDI Trimix Instructor
- PADI Staff Instructor
- Kiss Sidewinder Instructor
- PADI Tmx90 Instructor
- Cavern Instructor
From the water
Recent dives & projects
-
Expeditions
Lakshadweep, Meghalaya — projects pushing what Indian divers can do.
-
CCR & Technical
Sidewinder rebreather, trimix, sidemount — the rig and the discipline.
-
Deep & Decompression
Working past 60 m on open circuit and CCR. The numbers, the conservatism, the execution.
-
Fundamentals
Buoyancy, trim, propulsion — the foundations every diver needs and almost nobody is taught.
Training & Courses
View all courses →From the Depth Notes
Read all posts →How Decompression Models Work
May 28, 2025 · 14 min read
Your dive computer turns invisible dissolved gas into a single ascent number. Behind it sits a piece of bookkeeping: 16 imaginary compartments, the half-times that define them, and the M-values that decide when it's safe to come up.
CNS Oxygen Toxicity
May 31, 2025 · 14 min read
Why the oxygen that keeps you alive can trigger a seizure underwater: what's really happening in your brain, the numbers that keep you safe, and why the famous warning signs don't actually warn you.
Fit to Dive
June 9, 2025 · 9 min read
How chronic conditions like asthma, diabetes, and heart disease interact with diving, why proper assessment matters more than any checklist, and what real-world dive fitness actually looks like.
Dive Computers: How They Actually Work
June 5, 2025 · 8 min read
What your dive computer is really doing under the display: how it remodels your nitrogen every few seconds, what each reading means, and the setup mistakes that turn a safety tool into a liability.
Ready to go deeper?
Talk to me about your next course, rebreather training, or expedition.
Start a Conversation