Safety · Destination Guide
Trat And The Koh Chang Archipelago Thailand
Wrecks, coral gardens, and slow-island beach days in Thailand's eastern Gulf
Updated Jan 23, 2026 • 16 sources
Safety And Conservation
Most dives and snorkel sessions are on shallow reefs, but the area is still remote and seasonal. Treat the monsoon as a real planning factor, use surface signaling on every boat dive, and keep deep wreck profiles conservative.
Top Risks
- Primary risk: Monsoon sea crossings and cancelled boats
- Secondary risk: Wreck depth and overhead temptation
- Emergency contact: Thailand Tourist Police (1155)
- Safety overview: Most dives and snorkel sessions are on shallow reefs, but the area is still remote and seasonal.
Dive safety
- Deep wreck caution: The HTMS Chang wreck sits in a deep range and can tempt divers into overhead areas. Stay within training, plan gas carefully, and avoid penetration without a qualified guide and proper equipment.
- Surface signaling: Carry an SMB and whistle; boat traffic is common near park islands and popular bays.
- Weather and crossings: In May to October, sea state can change fast. Listen to operator calls, and do not pressure crews to run exposed routes.
- Buddy and separation: Visibility can vary. Use lights on deeper dives, agree on separation limits, and practice calm ascents.
- Freediving safety: Use a buoy and a trained buddy. Avoid breath-hold drops near busy boat zones.
- On-island care: Koh Chang and Koh Kood have clinics and basic medical services for minor issues.
- Serious incidents: Expect evacuation to mainland Trat or onward to Bangkok-level facilities depending on the case.
- Dive emergencies: Call Thailand emergency medical services (1669) and coordinate with your operator and dive insurance provider (for example DAN) for evacuation and chamber referral.
Snorkel and freedive safety
Monsoon sea crossings and cancelled boats
From roughly May to October, wind and rain can make crossings rough and cause same-day cancellations. Build buffer days and avoid tight connections between islands.
Wreck depth and overhead temptation
The wreck profile is deep and narcosis and gas consumption can surprise newer divers. Do not enter overhead spaces without proper wreck training and a team plan.
Scooter safety on steep roads
Koh Chang roads can be steep and slick after rain. If you rent a scooter, wear a helmet, avoid night rides, and choose a bike you can comfortably handle.
Sun, heat, and dehydration
Snorkel days are exposed. Use a rashguard, rehydrate aggressively, and plan shade breaks to avoid heat stress.
Wildlife and protected areas
- National park ethics: Many reefs sit inside Mu Ko Chang National Park. Follow ranger instructions, pay required fees, and keep the receipt.
- No-touch diving: Maintain buoyancy, do not touch or stand on coral, and never chase turtles or other wildlife for photos.
- Reduce impact: Use reef-safe sunscreen, secure gauges and octos to prevent dragging, and refuse single-use plastics on boat days.
Do Not Do This
Avoid entering when monsoon sea crossings and cancelled boats. Confirm local briefings before committing.
Emergency contacts
| Contact | Role | Phone | Availability |
|---|---|---|---|
| Thailand Tourist Police | Assistance for tourists, reporting issues, coordination | 1155 | 24/7 |
| Thailand Emergency Medical Services | Ambulance and medical emergency response | 1669 | 24/7 |
| Thailand Police Emergency | Police emergency line | 191 | 24/7 |
| Mu Ko Chang National Park | Park office contact (local coordination) | +66 39 510 928 | Office hours vary |