Safety · Destination Guide
Key Largo
America's first undersea park meets easy reef days and legendary wrecks
Updated Dec 13, 2025 • 12 sources
Safety And Conservation
Key Largo is a protected-reef destination with boat diving norms. Safety and conservation are linked: stable buoyancy, correct mooring use, and strict no-touch behavior protect both divers and coral. Plan conservatively around weather and current, especially for wreck days.
Top Risks
- Primary risk: Cold fronts can cancel boats
- Secondary risk: Hurricane-season flexibility
- Emergency contact: Emergency Services (911)
- Safety overview: Key Largo is a protectedreef destination with boat diving norms.
Dive safety
Operational Realities
- Most dives are from boats on fixed moorings.
- Reefs are often mild, but wrecks can have stronger current and deeper profiles.
Practical Safety Steps
- Carry an SMB and know how to deploy it.
- Use the mooring line and follow the captain's procedure for descent and ascent.
- If you are new to current or deep profiles, stay on reefs until conditions are easy and you have the right training.
- For snorkeling and freediving, use a float and flag where appropriate and avoid surfacing away from your group.
Environmental Hazards
- Fire coral can sting.
- Seasonal jellyfish are possible.
- Sun exposure is intense year-round.
If Something Goes Wrong
- Call 911 for emergencies.
- For suspected decompression illness or dive-related injury, contact DAN for consultation and evacuation guidance.
Local Care Considerations
The Upper Keys are served by local emergency services and hospital care. Mariners Hospital in the Upper Keys has hyperbaric services and is the usual regional reference point for dive injuries. Always confirm your operator's emergency action plan and closest chamber routing during the trip briefing.
Snorkel and freedive safety
Cold fronts can cancel boats
Winter cold fronts can bring fast-changing wind and rough seas. Keep a backup plan for bayside paddling, museums, or the REEF center.
Hurricane-season flexibility
Hurricane season runs June to November with peak risk in late summer and early fall. Build buffer days and book refundable options when possible.
Fire coral and stinging organisms
Fire coral can sting and seasonal jellyfish are possible. Wear a rashguard, maintain buoyancy, and avoid contact with the reef.
Boat traffic at shallow landmarks
Popular snorkel sites can get busy. Stay close to your guide, use a flag where required, and do not surface away from the group.
Wildlife and protected areas
Key Rules to Follow
- Sanctuary mooring buoys exist to prevent anchor damage. Use them whenever available.
- In Sanctuary Preservation Areas, fishing and collecting are prohibited and touching or standing on living or dead coral is prohibited.
- Anchoring on coral is prohibited and do not anchor when a mooring buoy is available.
Why It Matters Right Now
South Florida reefs experience heat stress and coral bleaching risk when water temperatures rise. In the warmest months, treat every dive as a low-impact dive: perfect buoyancy, no contact, no chasing wildlife, and careful finning to avoid sand and coral.
How to Contribute
- Visit and support local education and conservation organizations like REEF.
- Participate in cleanups and invasive-species awareness events when available.
- Choose operators that brief and enforce reef-safe behavior.
Do Not Do This
Avoid entering when cold fronts can cancel boats. Confirm local briefings before committing.
Emergency contacts
| Contact | Role | Phone | Availability |
|---|---|---|---|
| Emergency Services | Police, fire, medical emergency | 911 | 24/7 |
| Divers Alert Network (DAN) Emergency Hotline | Dive medicine consultation and evacuation guidance | +1-919-684-9111 | 24/7 |
| Florida Fish and Wildlife Conservation Commission (Wildlife Alert) | Report injured wildlife, violations, and wildlife conflicts | 888-404-3922 | Hotline |
| Florida Keys National Marine Sanctuary | Sanctuary information and reporting non-urgent issues | +1-305-809-4700 | Business hours (non-emergency) |