Home Hobbies How Long Can Scuba Divers Stay Underwater? 

How Long Can Scuba Divers Stay Underwater? 

How Long Can Scuba Divers Stay Underwater? 

Because humans cannot breathe underwater like fish, you will need to hold your breath if you intend to spend a significant amount of time below the surface. When kids play in the pool, lake, or even the bathtub, it’s not long before a competition to see who can hold their breath the longest underwater breaks out.

On a 40-foot dive, a typical open water qualified diver using a basic aluminum 80-cubic-foot tank will be able to stay down for around 45 minutes before emerging with a safe reserve of air. Aleix Segura of Spain now holds the Guinness World Record for retaining your breath underwater for a massive 24 minutes and 3 seconds.

Intense athletes known as free divers compete in such events on a regular basis. This is referred to as “static apnea.” Apnea is a momentary cessation of breathing, which free divers practice to enhance the length of time they can remain underwater without coming up for air.

Being submerged also aids in combating the body’s natural responses. When we dive underwater, our bodies, like dolphins and whales, naturally preserve oxygen. This response, known as the diving reflex, serves to save oxygen within our bodies and allows us to hold our breath for extended periods of time.

Keep reading to find out more. 

What Factors Determine How Long the Air in a Scuba Tank Will Last?

Tank Capacity

The aluminum 80-cubic-foot tank, which stores 80 cubic feet of air pressurized to 3000 pounds per square inch, is one of the most frequently used tanks in recreational diving. 

Scuba tanks, on the other hand, come in a variety of sizes and materials to suit a wide range of purposes (learn more about the difference between steel and aluminum tanks). 

Divers who go deep or for lengthy periods of time may prefer tanks with a larger internal volume. Petite divers who utilize little air may prefer smaller tanks for comfort. 

If all other things remain constant, a tank with a larger capacity of air will live longer underwater.


The pressure surrounding a scuba diver increases as he dives (learn how depth effects pressure in scuba diving). 

The air within the diver’s scuba tank is already compressed to a very high pressure, and the scuba tank is a hard container, so the pressure rise has no impact. 

The water pressure, on the other hand, compresses the air that left the tank and passes through the scuba diver’s regulator hoses and second stages. 

Due to water compression, the amount of air that fills 1 cubic foot of space at the surface will only fill 12 cubic feet of space at a depth of 33.

The Rate of Air Consumption

If all other conditions remain constant, a diver’s air consumption rate, also known as his Surface Air Consumption Rate (SAC rate) or Respiratory Minute Volume (RMV), will influence how long the air in his tank will last in comparison to the typical diver.

 A diver with a large lung capacity (tall or huge person) will require more air than a petite or short diver with a lower lung volume and will often use more air. 

Anxiety, qualification and experience, buoyancy management, and the amount of exercise the diver conducts during a dive all have an impact on an individual’s air consumption rate. 

A diver’s best bet for lowering his air consumption rate is to breathe slowly and deeply.

How Long Can Navy SEALs Hold Their Breath Underwater? 

Navy SEALs can hold their breath for up to three minutes underwater. Breath-holding drills are commonly used to prepare a swimmer or diver, as well as to boost confidence when swimming in high-surf situations at night. 

The Navy’s “two-man rule” — training with a buddy — is meant to lessen danger since each swimmer is aware of the other’s actions and may administer help if necessary. It’s been emphasized that a swim companion couldn’t reduce the risk inherent in breath-holding, especially if he is swimming himself. 

The Navy’s mission now is to improve safety guidelines and raise awareness about the danger of both swimmers experiencing shallow-water blackout when concurrently holding their breath.

How Long Can You Last With Scuba Gear?

Quality diving equipment can survive for years if properly maintained, but it is not intended to last forever. Equipment failure accounts for 15% of scuba diving deaths. Unfortunately, these issues are primarily the result of poor maintenance and incorrect equipment use.

As a general guideline, if your gear makes diving more challenging or unpleasant, irrespective of its state, fix or replace it. Dive gear that requires continual adjustment or does not fit makes a dive unpleasant at best and unsafe at worst. Continue reading for a list of reasons to replace frequently owned diving equipment.

The mask strap is often the first component of a mask to fail. If your mask no longer sticks to the surface of your face, it’s time to change it. The mask skirt is usually the next portion of a mask to wear out after the strap. 

The skirt is essential for keeping a strong seal around your face. When you’re not in the water, test your seal by pressing the mask against your face without the strap across the back of your head. If your mask no longer sticks to the surface of your face, it’s time to change it.

A scuba regulator’s duty is to provide you with breathing gas while you’re underwater. It’s undoubtedly the most important piece of diving equipment. Because you can’t see the moving bits within a reg, it might be difficult to discover faults. As a result, it’s vital to get your regulator serviced at least once a year.

Bring in any hoses that have cracks or bulges. Plastic cracks, no matter how tiny, are also a reason for alarm. Finally, a free-flowing or hard-breathing reg should be evaluated as soon as possible.


Scuba divers are ultimately restricted by how long they can stay underwater. Many factors must be considered, but the most likely cause is that your scuba tank will ultimately run out of air. 

When your tank hits 500 psi (50 bar, or roughly 20% remaining), you may begin your climb. If you were diving recreationally at a depth of 12 m (40 feet), it would take 45-60 minutes for your tank to empty.