Scuba diving with asthma has long been a contentious issue. Previously, a history of asthma automatically disqualified someone from diving. However, recent shifts in opinion now allow for a more individualized approach. 

Many diving doctors no longer see asthma as an absolute barrier. Instead, potential scuba divers with asthma should be assessed on a case-by-case basis. Doctors will evaluate the type and severity of asthma, the individual’s history of attacks, and the triggers.

Those with a history of asthma must consult with a diving doctor and undergo regular lung evaluations before scuba diving.

What Is Asthma?

Asthma is a condition that causes the airways to narrow in response to certain triggers. Individuals with asthma may have attacks when exposed to allergens, cold temperatures, during exercise, or under significant stress.

Asthma is widespread, as several studies estimated that about 8% of adults in the United States have been diagnosed with it at some point. Some people experience asthma in childhood and eventually outgrow it, while others may suffer from it later in life.

Why is Asthma Considered a Risk During Scuba Diving?

During an asthma attack, the airways constrict, leading to reducing their diameter and making it harder for air to flow in and out of the lungs. This increased friction results in greater effort needed for breathing.

The air divers breathe underwater is compressed due to the pressure, making it denser and harder to inhale and exhale compared to surface air. Imagine breathing through a pipe: at depth, it’s like trying to suck honey through a pipe.

The deeper a diver goes, the denser the air, and the more resistance they face while breathing. When combined with the increased breathing resistance during an asthma attack, it can become difficult for a diver experiencing an asthma attack underwater to get enough air.

As a diver ascends, the air in their lungs expands due to the reduced water pressure. For non-asthmatic divers, this isn’t an issue as the expanding air is expelled during exhalation.

However, a diver experiencing even a mild asthma attack may struggle to release the air from their lungs at a normal rate because their airways are constricted. This can trap expanding air in the lungs, potentially causing decompression illness, which can have severe or even fatal consequences.

Scuba diving with asthma poses greater risks than regular exercise with asthma because of the unique challenges of diving. Underwater, divers cannot immediately stop exercising or use a rescue inhaler.

Is Asthma a Complete Barrier to Scuba Diving?

In some cases, scuba diving with asthma may be available, depending on the type of asthma and their medical history. Scuba divers with asthma should consult a diving doctor, undergo regular lung tests, and thoroughly understand the risks associated with scuba diving with asthma before deciding.

Assessing an Asthmatic’s Diving Fitness

Doctors assess the type of asthma, frequency of attacks, medication, and personal history of a potential diver. Asthma that is triggered by exercise, stress, or cold is generally considered a complete contraindication for diving, as these triggers are commonly encountered underwater.

Asthma which is triggered by allergens like pollen or cat hair isn’t usually contraindicated with scuba diving, as divers will never encounter these allergens while diving.

Divers who use asthma medication may still be allowed to dive if their asthma is well-controlled. Certain medications are approved for diving. A diving doctor will assess the medication type and its effectiveness in preventing asthma attacks before giving clearance for scuba diving.

Why Are Physical Tests Crucial in Assessing Diving Fitness for Asthma Patients?

Physical tests are essential for assessing lung health and determining fitness to dive. Even people with few or no recent asthma attacks may not be fit for scuba diving if they have an issue in their lungs. Beware of doctors who give a blanket “no” or “yes” without conducting a physical evaluation.

Should You Practice Scuba Diving With Asthma?

The choice to dive with asthma should be reached by you and your doctor after thorough testing and consideration of all factors related to scuba diving with asthma.

Is Snorkeling Risky for Individuals with Asthma?

Snorkeling poses less risk for individuals with asthma compared to scuba diving. This is primarily because snorkelers do not breathe in compressed air at depth, reducing the risk of lung over-expansion during ascent.

However, it’s essential that a person’s asthma is stable and well-controlled, as accidental inhalation of water and the physical exertion of swimming against currents can still trigger an asthma attack. Interestingly, many exceptional underwater videos and films have been created by snorkelers using just a snorkel, mask, and handheld camera.