Certified Hyperbaric Technologist Practice Test

What is a crucial factor in preventing decompression sickness?

1. Maintaining hydration

2. Breathing enriched oxygen

3. Ascending at controlled rates

4. Increasing dive time

The correct answer is: Ascending at controlled rates

Ascending at controlled rates is a crucial factor in preventing decompression sickness because it helps the body to safely equalize the pressure changes experienced during a dive. As a diver ascends, the ambient pressure decreases, which can lead to dissolved gases—primarily nitrogen—that have accumulated in the tissues and blood under higher pressure being released. If a diver ascends too quickly, these gases can form bubbles in the bloodstream and tissues, leading to decompression sickness, commonly known as "the bends." Controlled ascent allows the body sufficient time to eliminate these gases through respiration and metabolic processes, reducing the risk of bubble formation. Divers typically follow recommended ascent rates and may employ safety stops at certain depths to allow for further off-gassing of nitrogen. This process is essential for preserving the diver's health and safety during and after dives. Hydration is important for general well-being and may support better physiological function during dives, but it's not the primary preventive measure against decompression sickness itself. Breathing enriched oxygen and increasing dive time can also be relevant in specific contexts, but they do not directly correlate to minimizing the risk of decompression sickness in the same way that controlled ascent does.