Snorkeling

Is snorkeling safe?

For a healthy swimmer in calm water with a buddy, yes, very. The trouble is that many of the people who snorkel on holiday are not in that group. In Hawaii, snorkeling is the most common activity among visitors who drown: 87 deaths in 2019–2023, more than swimming, surfing or scuba diving.

Set against the number of people who snorkel, that comes to about 6 deaths per million visitors who snorkel during a Hawaii holiday. Queensland's reefs look worse: about 12 deaths per million overseas visitors who snorkel there, or roughly 5 to 6 per outing, partly because Queensland also counts heart deaths. We use the middle, about 9 micromortsMicromortA one-in-a-million chance of death. It lets you compare the risk of very different activities on one scale.More in the glossary per holiday, roughly two skydives (about 4 each). The risk is real but small for any one swimmer, and it falls heavily on older first-timers.

Where the Hawaii figure comes from

The Hawaii Department of Health counted 202 ocean drownings among non-residents in 2019–2023. Snorkeling accounted for 43% of them. Of the 87 snorkel victims, 75 came from other US states and 12 from abroad, and 38 drowned off Maui. The average yearly number of visitor snorkel drownings rose more than eightfold from 1995–1999 to 2015–2019, while visitor arrivals grew by about half.

For the denominator, the state's 2024 visitor survey found that 40.1% of US visitors snorkeled during their stay. Domestic flights brought about 32 million visitors in 2019–2023, so roughly 13 million of them snorkeled. Seventy-five deaths among US visitors is 5.8 per million, and all visitors together give about 6. Domestic flights also carry some foreign visitors, so this mixes two groups slightly.

Two caveats. The survey share is from 2024, and we apply it to the earlier years. And the count covers deaths with drowning as the underlying or a contributing cause, so a snorkeller whose death certificate records only heart disease is missing. Both make our figure a little uncertain; the second makes it, if anything, too low.

Queensland gives a check. Tourism Research Australia estimates that about 430,000 overseas visitors a year snorkelled in Queensland in 2005–2019, and 81 died over those 15 years, or 1.25 deaths a year per 100,000 snorkellers. That count includes heart deaths, which may explain part of the gap with Hawaii. A 2006 survey counted more than 1.1 million snorkel outings by more than 500,000 overseas visitors, a little over two each, so per outing the risk is roughly 5 to 6 micromortsMicromortA one-in-a-million chance of death. It lets you compare the risk of very different activities on one scale.More in the glossary.

Who dies snorkeling

The pattern is consistent across countries. In Hawaii, visitors who drowned while snorkeling were 58 on average, against 52 for other visitors who drowned, and 76% were men. In Queensland, John Lippmann's review of 2000–2019 found a median age of 59 among 166 snorkel deaths, 83% men, and two-thirds overseas tourists. Health conditions that likely contributed were found in 61% of them.

The main disabling event in Queensland was heart-related. Lippmann's 2025 review of 317 Australian snorkel and breath-hold deaths found that about a third of victims were likely disabled by a heart rhythm problem, often with heart disease or a thickened heart muscle. In younger breath-hold divers the pattern is different: blackout after a long breath-hold, which our free-diving page covers.

A snorkel-safety panel of the Hawaii health department's drowning committee also describes two drowning mechanisms in healthy-looking swimmers. One is water entering the snorkel and being inhaled. The other is a fast build-up of fluid in the lungs, linked to breathing hard against the resistance of the snorkel tube.

Why snorkellers drown unnoticed

A snorkeller in trouble does not look like one. They float face down, which is exactly what everyone else is doing. A 2021 review of studies from several countries found that 50–100% of those who drowned were snorkelling alone or had separated from their buddy or group. By the time someone notices, minutes have passed.

That is also why a lifeguarded beach helps less than it seems. In April 2026 a 66-year-old woman died after a snorkeling incident at Hanauma Bay, a lifeguarded bay on Oahu; lifeguards found her about 10 feet from shore.

How to snorkel more safely

1. Be honest about your health. If you have heart disease, high blood pressure or get short of breath on exertion, talk to your doctor before a snorkelling holiday. Tour operators in Queensland ask health questions for this reason.
2. Practise first. Try the mask and snorkel in a pool or standing depth before swimming out. Clear the tube with a sharp blow and learn to lift your head and breathe normally.
3. Wear a snorkel vest and inflate it partly. It lets you rest without effort.
4. Stay within arm's reach of a buddy, and look up every minute or two.
5. Stop at the first sign of trouble. Shortness of breath, coughing, chest pain or feeling unusually tired are reasons to lift your head, roll onto your back and signal for help.
6. Check conditions. Choose calm water and ask a lifeguard about currents and surf before you get in.
7. Skip alcohol before getting in the water.

How we scored it

Fatality risk (64) rests on about 9 micromortsMicromortA one-in-a-million chance of death. It lets you compare the risk of very different activities on one scale.More in the glossary per snorkelling holiday: the middle of Hawaii's 6, which leaves out heart deaths, and Queensland's 12, which includes them. Injury risk (85) is low apart from drowning itself. Controllability (65) and rescue (65) are held down by heart events that skill cannot prevent and by the way a drowning snorkeller blends in. Per outing the risk is probably one to three times a scuba dive, and well above swimming laps in a pool; see open-water swimming for comparison.