What contributed to the diver's loss of consciousness in the confined space incident?

• A. Oxygen deficiency
• B. Gas leak
• C. Nitrogen blanket
• D. Carbon dioxide buildup

Answer: (C)

The main idea is that an inerting nitrogen blanket reduces the amount of breathable oxygen in the space. When nitrogen fills the confined area, it displaces oxygen, lowering the oxygen partial pressure available to the diver. Breathing air with less oxygen means brain cells aren’t getting enough oxygen, so function slows, coordination and judgment falter, and consciousness can be lost as the brain becomes starved for oxygen. This specific situation is about oxygen being diluted by inert gas, not about breathing nitrogen at depth (nitrogen narcosis) or about a buildup of carbon dioxide.