Which factor does NOT contribute to the risk of nitrogen narcosis?

The factor that does not contribute to the risk of nitrogen narcosis is the temperature of the water. Nitrogen narcosis, often referred to as "rapture of the deep," primarily arises from the effects of increased partial pressure of nitrogen on the body at greater depths. As a diver descends, the concentration of nitrogen in the bloodstream increases due to the higher pressures, leading to alterations in mental and physical functioning.

While depth of dive is a direct contributing factor, as it increases the partial pressure of nitrogen, and personal tolerance to nitrogen varies between individuals, influencing their susceptibility to narcosis, the time spent underwater can also factor into the overall experience. However, water temperature does not have a direct effect on nitrogen narcosis itself. While extreme temperatures can impact a diver’s overall comfort and physiological responses, they do not change the way nitrogen is absorbed into the body nor do they influence the narcosis risk directly.