SDI Open Water Scuba Diver Practice Exam

What happens to the perception of temperature as water pressure increases?

1. It feels warmer

2. It feels colder

3. It remains the same

4. It fluctuates slightly

The correct answer is: It feels colder

As water pressure increases, the perception of temperature often feels colder due to the way pressure affects the body's thermoregulation. When divers descend, they encounter increased pressure, which can lead to a phenomenon known as thermal conductivity. Water has a higher thermal conductivity than air, meaning it can conduct heat away from the body faster. At greater depths, the body is also subjected to cooler temperatures, and the sensation of cold intensifies not just from the actual temperature of the water but also because of how the body loses heat more rapidly under increased pressure. This combination of factors makes the water feel colder, enhancing the sensation of chill even if the temperature of the water itself hasn’t changed significantly. Understanding this principle is crucial for divers to prepare adequately for thermal protection, ensuring they use appropriate exposure suits to maintain body warmth during their dives.