What is one of the primary risks of diving at depths below 30 meters (100 feet)?

Diving at depths below 30 meters (100 feet) introduces the risk of increased nitrogen absorption, which can lead to a condition known as nitrogen narcosis. This phenomenon occurs because at greater depths, the higher partial pressures of nitrogen in the breathing gas can affect the central nervous system, producing intoxicating effects similar to alcohol. Symptoms can include impaired judgment, reduced coordination, and an altered mental state, all of which can significantly compromise a diver's ability to respond to emergencies or make sound decisions while underwater.

While reduced visibility and lower air pressure can be encountered at depth, they do not directly relate to the chemical effects of nitrogen in the body. Increased water temperature is generally not a concern at deeper depths, where temperatures can actually drop. Hence, understanding the physiological impacts of increased nitrogen absorption is crucial for divers exploring deeper waters, which is why this risk is a prominent consideration in diving safety and training.