Why do some divers feel cold faster than others in the same water? This chapter breaks down how body type, age, dive profile, and hydration affect heat loss—and how to choose thermal protection that actually works for you.

When a wetsuit is no longer enough, drysuits take over. Learn how drysuits work, why they outperform wetsuits in cold or extended dives, and when you should make the switch for better thermal control, safety, and performance underwater.