Nitrox Diver Learn to safely take advantage of the benefits of Nitrox for recreational diving. Nitrox allows you longer bottom times, due to its lower nitrogen content. Topics will include the history of Nitrox, physics, physiology, oxygen toxicity, dive planning, analysis and more. The course requires one classroom session and includes all classroom materials. This class is highly recommended for those interested in NC wreck diving. Open to all certified divers. Cost: $150