The PADI Deep Diver course is a specialty course designed for certified divers who want to explore deeper waters safely, typically up to 40 meters (130 feet), which is the recreational diving limit.

Here’s a quick overview of what you typically learn during the course:

1. Dive Planning: How to plan deep dives, including understanding no-decompression limits, contingency plans, and safety stops.

2. Gas Management: Monitoring and calculating your air consumption and ensuring you have adequate gas supply for deeper depths.

3. Nitrogen Narcosis Awareness: How to recognize and respond to symptoms of narcosis, which can impair judgment and coordination at depth.

4. Emergency Procedures: Skills for handling emergencies that may occur during deep dives.

5. Buoyancy Control: Fine-tuning buoyancy at depth, where changes in pressure have greater impact.

You usually do four dives over 2 days under instructor supervision to reinforce these skills.