No-Decompression Limit (NDL) Calculator
Look up no-decompression limits (NDL) by depth from PADI recreational dive tables.
Maximum bottom time before a decompression stop is required.
The No-Decompression Limit (NDL) is the maximum time you can spend at a given depth on a single dive without needing to make decompression stops on ascent. Exceeding the NDL means you must stop at specific depths to allow nitrogen to safely off-gas.
PADI recreational dive table NDLs (first dive, no prior dives):
- 10 m (33 ft): 219 min
- 12 m (40 ft): 147 min
- 14 m (47 ft): 98 min
- 16 m (53 ft): 72 min
- 18 m (60 ft): 56 min
- 20 m (66 ft): 45 min
- 22 m (72 ft): 37 min
- 25 m (82 ft): 25 min
- 30 m (99 ft): 20 min
- 40 m (132 ft): 10 min
Safety stop: Always perform a 3-minute safety stop at 5 m (15 ft) before surfacing, even if within NDL. This is not mandatory but reduces risk of decompression sickness significantly.
Repetitive dives: After a dive, residual nitrogen in your tissues means your NDL for the next dive at the same depth is shorter. Dive computers handle this automatically.
Decompression sickness (DCS): Caused by nitrogen bubbles forming in tissues on rapid ascent. Symptoms: joint pain, skin mottling, numbness, shortness of breath. Treatment: hyperbaric oxygen chamber. Never dive alone — a buddy can spot early DCS symptoms.
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