St Thomas and St John

For scuba, maintain certification limits and conservative depth, air and no-decompression planning; use a buddy and appropriate surface signaling; do not penetrate wrecks, arches or caves without specialized training, equipment and permission. Currents at rock/cay sites and winter swell demand operator-led selection. NPS prohibits scuba inside the Trunk Bay boat-exclusion area and prohibits snorkeling/scuba in marked boat navigation channels and certain restricted areas. For freediving, qualified rescue-capable supervision and a trained buddy are essential, with no solo breath holds or hyperventilation. For snorkeling, assess entry/exit and swim length honestly, especially Waterlemon Cay north side and Hawksnest shallow coral. The formal Atlantic hurricane season is June 1 through November 30; weather can close ports or charter departures. Check the DPNR coastal water-quality advisory after rain, not just visibility. Use DAN/training-agency recommendations for flying after scuba.

Call 911 for an active medical emergency. St John has the Myrah Keating Smith Community Health Center, which advertises 24-hour emergency capability, and St Thomas has the Roy Lester Schneider Hospital. Severe injuries, diving illness or specialized treatment may require stabilization and transfer, possibly off-island. No functioning local recompression chamber or guaranteed air-evacuation capacity was independently confirmed. DAN explicitly warns that public lists cannot guarantee current chamber availability; involve local emergency clinicians and DAN (+1 919 684 9111) for diving illness assessment, treatment routing and evacuation coordination. Maritime emergencies can be reported on VHF channel 16 through the US Coast Guard. Confirm emergency oxygen, first aid, communications and evacuation arrangements with the booked instructor or boat captain.

Virgin Islands National Park and the adjacent Coral Reef National Monument protect coral reefs, seagrass beds, mangroves and sea turtle habitat. The current NPS compendium governs mooring, anchoring, boats, commercial operations, no-entry zones and snorkeling/scuba access; never drop an anchor on coral or rely on an outdated tour map. Keep fins and hands away from corals, stand only on sand, do not feed fish, and never pursue or touch turtles or rays. NPS warns that shallow elkhorn corals at Hawksnest are particularly fragile. USVI restricts several reef-harming sunscreen chemicals; use appropriate mineral sun protection and cover up. Respect marked turtle-nesting habitat, limit beach lights and pack out all litter. DPNR water-quality advisories and NPS closure alerts can change local access.