Most dive destinations make you think about flying after diving once: on the last day. Hawaiʻi makes you think about it all week. The islands are connected by short flights, and the roads climb from the reef to some of the highest drivable elevations in the Pacific within an hour or two. A sunrise trip to Haleakalā, a drive across Saddle Road or an evening at the Maunakea visitor station can put more altitude stress on a recently dived body than the flight home.
This guide sets out what Divers Alert Network (DAN) recommends, how high Hawaiʻi's roads actually go, and a simple way to schedule your trip so the mountains and the reef never collide.
- One no-decompression dive
- 12 hours
- Repetitive dives or multi-day diving
- 18 hours
- Dives with decompression stops
- Substantially longer than 18 h
- Altitudes the guidelines cover
- 2,000 to 8,000 ft
What DAN Actually Says
DAN's guidelines for flying after recreational diving come from a 2002 workshop and decades of chamber trials. For divers without symptoms of decompression sickness (DCS) going to cabin altitudes of 2,000 to 8,000 feet, they recommend a minimum surface interval of 12 hours after a single no-decompression dive and 18 hours after multiple dives per day or multiple days of diving. After dives that required decompression stops, DAN says there is little evidence to base a number on but that an interval substantially longer than 18 hours is prudent; DAN's travelers' guide uses 24 hours.
Two caveats from DAN matter in Hawaiʻi. First, the guidelines reduce risk but do not guarantee you will avoid DCS; the trials were done with resting, dry volunteers, and real divers who worked hard in the water may need longer. Second, DAN notes that any post-dive ascent to altitude, including by car, increases decompression stress. The guidelines were built around airliner cabins, which are pressurized to an equivalent of up to about 8,000 feet. Several of Hawaiʻi's roads go higher than that.
How High Hawaiʻi's Roads Go
| Place | Island | Elevation | Notes |
|---|---|---|---|
| Maunakea summit | Hawaiʻi Island | 13,796 ft | Highest point you can drive to in Hawaiʻi; 4WD road above the visitor station. |
| Hawaiʻi Volcanoes National Park | Hawaiʻi Island | Sea level to about 13,680 ft | The Kīlauea summit area most visitors drive to sits several thousand feet up. |
| Haleakalā summit (Puʻuʻulaʻula) | Maui | 10,023 ft | Highest point on Maui; popular for sunrise. |
| Haleakalā Visitor Center | Maui | About 9,740 ft | Sunrise viewing area below the summit. |
| Maunakea Visitor Information Station | Hawaiʻi Island | About 9,200 ft | Standard stop for acclimatization and stargazing. |
| Haleakalā Headquarters Visitor Center | Maui | About 7,000 ft | Just past the summit entrance station. |
| Saddle Road high point | Hawaiʻi Island | About 6,632 ft | Daniel K. Inouye Highway, the fast route between Kona and Hilo. |
| Kalalau Lookout, Kōkeʻe State Park | Kauaʻi | About 4,000 ft | Top of the Waimea Canyon road; the park spans roughly 3,200 to 4,200 ft. |
For comparison, the DAN guidelines were tested for exposures up to 8,000 feet. Haleakalā's summit and visitor center, the Maunakea visitor station and the Maunakea summit are all above that range, and the drive from the coast takes about two hours or less. There is no published DAN interval specifically for driving to 10,000 or 14,000 feet. The conservative reading is to treat these drives as at least as demanding as a flight, and to give them more time, not less.
Surface Interval Calculator
Enter when your last dive ended and the kind of diving you did. The calculator adds the DAN minimum interval and gives you the earliest time to fly or drive above about 2,000 feet. It is a scheduling aid, not medical advice, and it does not replace your dive computer's no-fly time; use whichever is longer.
Island by Island
Maui: Haleakalā
The summit sunrise is one of Maui's most popular outings, and it usually means leaving in the small hours to drive from sea level to 10,023 feet. If you have been diving Molokini or the Cathedrals the day before, that drive falls inside the DAN window for repetitive diving. Do Haleakalā on your first full day on Maui, before your first dive, or on the day after your last. Sunrise also requires a reservation from the National Park Service.
Hawaiʻi Island: Saddle Road, Maunakea and the volcano
Saddle Road is the direct route between Kona and Hilo and tops out at about 6,632 feet. Maunakea's visitor station is at about 9,200 feet and the summit at 13,796 feet. Hawaiʻi Volcanoes National Park extends from sea level to well over 13,000 feet, and the Kīlauea summit area where most visitors spend their time sits several thousand feet above the coast. If you are diving in Kona, plan the volcano and the mountain for the start of your stay. If you must drive to Hilo after diving, the alternative highways around the north and south of the island also climb, so time it as you would a flight.
Kauaʻi: Waimea Canyon and Kōkeʻe
The canyon road climbs to about 4,000 feet at the Kalalau Lookout. That is lower than the Maui and Big Island summits but still a meaningful ascent after a morning of diving. Put the canyon on a non-dive day.
Oʻahu
Oʻahu's roads stay low; the issue here is inter-island and outbound flights.
Inter-Island Flights and Helicopter Tours
A 30-minute hop from Honolulu to Kona is still a flight, and the cabin is pressurized much like a long-haul jet. Apply the same intervals. On a two-island trip, the simplest plan is a dive-free morning before the hop: dive island one, rest, fly, then start diving on island two.
Helicopter and small-plane tours, popular over Kauaʻi's Nāpali Coast, Waimea Canyon and the Big Island's volcano, can climb well above sea level, often without cabin pressurization. Ask the operator how high the route goes and treat the tour as altitude exposure.
A Trip Plan That Avoids the Problem
- Arrive, then go up. Schedule Haleakalā, Maunakea, the volcano or Waimea Canyon on your first day or two, before you dive.
- Dive the middle of the trip. Keep dive days together.
- Leave a full dry day at the end. At least 18 hours after your last dive before you fly home; 24 hours is a common, simple rule many shops use.
- On two-island trips, fly between islands on a non-dive morning.
- Carry dive accident insurance and know where the chamber is.
If Symptoms Appear
Joint pain, unusual fatigue, numbness or tingling, skin rash, dizziness, or difficulty breathing after diving, especially if it starts or worsens on the way up a mountain or during a flight, may be DCS. Do not wait to see if it passes. Call 911, breathe emergency oxygen if it is available and tell responders about your dives. DAN runs a 24-hour emergency hotline for divers. Hawaiʻi's emergency recompression facility is the University of Hawaiʻi Hyperbaric Treatment Center at Kuakini Medical Center in Honolulu, which DAN designates as its Pacific regional coordination center; divers on other islands are flown to Oʻahu.
See the summit first. The reef will wait for you; nitrogen will not.