What is the recommended practice to prevent decompression sickness during ascent?

• A. Follow decompression table
• B. Hold breath during ascent
• C. Ascend rapidly
• D. Dive deeper first

Answer: (A)

Preventing decompression sickness during ascent hinges on controlling how nitrogen (or other inert gas) is eliminated from the body as pressure decreases. Following decompression tables (or a dive computer’s plan) provides the approved ascent rate and required decompression stops so bubbles don’t form as gases come out of solution. This method gives enough time for offgassing and keeps tissue pressures within safe limits.

Holding your breath while ascending is risky because it can cause lung overexpansion injuries and does not manage inert gas elimination. Ascending rapidly gives even less time for offgassing and increases bubble formation. Diving deeper first loads more inert gas into the tissues, making decompression heavier, not safer.