What protective gear is essential for maintaining body temperature underwater?

An exposure suit is essential for maintaining body temperature underwater because it is specifically designed to provide thermal insulation against cold water. These suits, which can be made from materials such as neoprene, minimize heat loss by trapping a thin layer of water between the suit and the body. This layer of water is warmed by body heat, helping to maintain a comfortable temperature during dives.

In contrast, a safety vest and a life jacket are primarily designed for buoyancy and flotation, rather than thermal protection. While they can enhance safety on the surface, they do not provide adequate insulation from cold water. A weight belt, although useful for helping divers achieve neutral buoyancy, also does not assist in temperature regulation. Therefore, the exposure suit stands out as the crucial protective gear for keeping divers warm and comfortable while submerged.