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Snorkel Safety Study Final Report

A primary purpose of the 'Snorkel Safety Study' is to determine common causes and major risk factors associated with snorkel-related fatal (and non-fatal) ocean drownings in Hawaii.

The focal points for this guide are the conclusions made in the official announcements about SI-ROPE (or Snorkel Induced Rapid Onset Pulmonary Edema).

What's the Safety Guidelines in Snorkeling?

Finding an explanation for the mysterious snorkel drownings, especially in Hawaii, was the main goal of the study.

Why?

Because, exact causes for an increasing number of snorkelers drowning in Hawaiian waters are not what they seem.

The most severe incidents are not attributed to being submerged (e.g. inhaling or ingesting sea water).

Instead, some recent case reports of accidents and incidents show that snorkelers' lungs are filling with body fluids - due to the type of snorkel tube used by the individual. So, the key question is are you a snorkeler at risk of suffering SI-ROPE?

Snorkel Safety Study and Technical Papers

The conclusions stated in the report are preliminary findings. As a result, further studies will help to verify the vital information and recommendations needed for future safety guidelines in snorkeling.

This particular study focused on (all):

Background
Findings and Conclusions Made
The Physiology of Snorkel Induced Rapid Onset Pulmonary Edema (SI-ROPE)
The Perceived Relationship between Rapid Onset Pulmonary Edema (ROPE) and Cardiac Dysfunction
Specific Factors Contributing to Snorkel Drowning in Hawaii

Reasonable Deductions

Snorkel Induced Rapid Onset Pulmonary Edema (SI-ROPE) is a common factor in snorkel-related drowning and near-drowning events. The major risk factors associated with the development of SI-ROPE include:

Certain types of pre-existing medical conditions.
Differential degree of a snorkel tube's resistance to inhalation.
Increased exertion carried out by the participant.

Furthermore, other important and significant factors found among the survey participants concluded that:

Aspiration (inhalation of salt water) was rarely the trigger, or even a major factor, in near drowning incidents while snorkeling.
Lack of swimming or snorkeling experience is rarely a factor in snorkelers who get into trouble.
Almost all events occurred in a place where the person was unable to make contact with the ocean floor.
38% used a full-face mask. 90% of those who wore a full-face mask considered it as being a contributing factor to their trouble.

Pro Tip: Our News section contains more information about whether full face snorkel mask deaths are linked with IPO (immersion pulmonary oedema).

The typical sequence of a SI-ROPE drowning was:

Sudden shortness of breath, fatigue, loss of strength.
A feeling of panic, doom, and the need to get assistance.
Diminishing consciousness.

The study identified the existence and process of SI-ROPE. But, it could not confirm a correlation between all fatal cases of snorkeling ROPE and recent prolonged air travel.

Expert Advice for Safer Snorkeling

In fact, the majority of snorkel related incidents occur quickly and without an obvious struggle. So, distinguishing between someone who is in distress and someone who is enjoying snorkeling can be difficult for observers.

Personal Safety Lies with the Snorkeler

As noted in the Snorkel Safety Study Final Report PDF, the primary task is to propose snorkel safety messages - not implement them. For example, simple ways to make snorkeling safer include:

Always swim with a buddy - and if you can't swim, do not go snorkeling.
Choose to buy the best snorkel devices that you can afford. Avoid tubes with constrictions in bore size or mouthpiece calibre. These may increase the likelihood of resistance to inhalation.
Snorkel in water where you can comfortably touch the bottom (e.g. no deeper than chest level).
If you have any doubts about your cardiovascular health - do not go snorkeling.
Check your location frequently so you don't drift away from your base.
Shortness of breath is often a sign of impending danger. Stay calm, remove the snorkel from your mouth, breath slowly and deeply, stand up, and exit the water without delay.

Recommended Proposals and Actions

Advise emergency responders of the SI-ROPE phenomenon and the likely involvement of pulmonary edema unrelated to aspiration in snorkel-related cases.
Develop a statewide public education program that addresses snorkeling safety, with special emphasis at places commonly used for snorkeling activities.

Disclaimer: Inexperienced and experienced swimmers should not consider recreational snorkeling as being a benign, low-risk activity. Visitors to Hawaii have an increased risk of drowning from snorkeling, relative to most other ocean sports.