• Currents and drift: Offshore parks like Abrolhos Marine National Park Brazil and Laje De Santos Brazil can have current. Carry an SMB.
• Upwelling and thermoclines: On the Southeast coast near Arraial Do Cabo Brazil, temperature can drop to 18°C to 22°C quickly.
• Boat traffic: Many dives and snorkel sessions run from small boats in busy bays.

Brazil has recompression chambers and advanced care in major coastal cities, but access can be limited in remote locations. For Fernando de Noronha and offshore liveaboards, plan conservative profiles and confirm evacuation pathways with your operator.

Brazil's protected areas include strict-protection parks and sustainable-use reserves under the national conservation-unit framework. In marine parks, expect rules such as no touching or collecting, no feeding, and limits on where operators may anchor or land.