Which statement about no-decompression dives is true?

Which statement about no-decompression dives is true?

• A. They require decompression stops on the ascent.
• B. They allow ascent directly to surface without mandatory stops if within no-decompression limits.
• C. They are only for deep dives over 100 feet.
• D. They require a surface interval of at least 3 hours between dives.

Answer: (B)

No-decompression dives are planned so you can surface directly without mandatory decompression stops as long as you stay within the no-decompression limit for your depth. The no-decompression limit is the maximum bottom time at a given depth that allows the inert gas (nitrogen) to off-gas gradually during the ascent without needing decompression stops. So staying within that limit means a direct ascent to the surface is acceptable. If you exceed the limit, you’d need decompression stops or a different dive plan, which is why this option is the true statement. In practice, dive computers or tables determine the limit, and you may still make a safety stop at about 5 meters. The other statements aren’t correct: no-deco dives aren’t defined by mandatory stops, they aren’t restricted to deep dives, and there isn’t a universal 3-hour surface-interval rule for no-decompression dives.

No-decompression dives are planned so you can surface directly without mandatory decompression stops as long as you stay within the no-decompression limit for your depth. The no-decompression limit is the maximum bottom time at a given depth that allows the inert gas (nitrogen) to off-gas gradually during the ascent without needing decompression stops. So staying within that limit means a direct ascent to the surface is acceptable. If you exceed the limit, you’d need decompression stops or a different dive plan, which is why this option is the true statement. In practice, dive computers or tables determine the limit, and you may still make a safety stop at about 5 meters. The other statements aren’t correct: no-deco dives aren’t defined by mandatory stops, they aren’t restricted to deep dives, and there isn’t a universal 3-hour surface-interval rule for no-decompression dives.