Flying after diving — 12, 18 or 24 hours? The actual DAN guidance

In one paragraph

Per [DAN's current guidance](https://dan.org/health-medicine/health-resource/health-safety-guidelines/guidelines-for-flying-after-diving/): wait **at least 12 hours** after a single no-decompression dive, and **at least 18 hours** after multiple dives or multiple consecutive days of diving. For decompression dives (rare in recreational diving), substantially longer — 24+ hours. The 12-hour minimum is a safety floor; many divers wait the full 18-24 hours regardless because the cost of caution is one extra night, the cost of decompression illness mid-flight is severe.

Why even short flights matter

Commercial cabins pressurise to 6,000–8,000 ft equivalent — meaningfully lower pressure than sea level. After a dive, your tissues still hold residual nitrogen. Lower pressure means that nitrogen wants to come out of solution and form bubbles. The 12 / 18 hour wait gives your body time to off-gas through normal respiration. Note: the boat ride back to Bali by fast boat is at sea level — no problem. The flight from Lombok or Bali to your next destination is where the rule applies.

Planning your last-day-on-Gili-Air schedule

Standard rule of thumb if you have a flight: **no diving on your final day**. If you must dive late, choose a morning shallow dive (max 12 m) and aim for at least 18 hours before your flight's scheduled takeoff. Practical example: last dive Tuesday 10:00 → Wednesday afternoon flight from Lombok is fine; same dive → Wednesday morning flight is too tight. We block all bookings for the final day automatically on multi-dive packages.

Common questions

Does the 12/18-hour rule apply to my boat ride back to Bali?

No. The boat travels at sea level — same pressure as where you dive. You can dive in the morning and take an afternoon fast boat to Bali safely. The rule only applies to flights or any ascent to altitude (a Bali volcano hike, a road trip to Ubud's rice terraces at 600 m elevation can also count if it's same-day after deep diving).

What if I exceed the wait time anyway — am I safe?

Yes — the 12/18 hour rule is a minimum, not a maximum. Waiting 24-48 hours after your last dive is completely fine. Once the residual nitrogen has off-gassed (within ~24 hours for recreational dives), the risk returns to baseline.