Are Submarine Tours Safe?

On June 18, an experimental submersible, carrying a pilot and four passengers to the wreck of the Titanic, went missing. After several days of search efforts, authorities concluded that the sub, OceanGate Expedition’s Titan, had experienced a catastrophic implosion, resulting in the loss of all lives on board.

This incident has understandably raised public anxiety about the submarine industry, prompting travelers who have booked or are considering sub trips to rethink their plans. But should this worry be justified?

Feeling a bit apprehensive about diving in a submarine or submersible is natural, as these are confined environments that take you underwater. However, there’s generally not much to be concerned about.

“A certified submarine is much safer than what people usually think. Yes, there are risks when boarding a submarine, just like there are when flying or driving,” says Mckenzie Margarethe, a marine naturalist and former submarine copilot for Atlantis Submarines. “However, with most touring submarines, issues are rare. Every potential danger has been assessed, and an emergency plan is created, with the crew regularly trained to ensure they are prepared.”

Here’s what you should know before booking a submarine or submersible tour.

What occurred with the “Titan”?

The Titan was an experimental submersible created by OceanGate Expeditions, intended to take tourists to the wreck of the Titanic, located about 12,500 feet deep in the North Atlantic Ocean. On June 18, during a planned dive, the expedition team lost communication with the sub, leading to a multi-day search-and-rescue operation by international teams. Debris from the sub was located by a remotely operated vehicle (ROV), suggesting that the vessel experienced a catastrophic implosion that resulted in the deaths of all five individuals on board, including OceanGate CEO Stockton Rush, who was piloting the sub. While investigations are still ongoing, it’s suspected that the sub’s pressure hull, which is designed to hold passengers under pressure, failed, causing it to implode under the immense water pressure.

What distinguishes a submarine from a submersible?

Both submarines and submersibles are types of underwater vessels. Submarines can navigate independently, meaning they can enter and exit ports under their own power. Submersibles, on the other hand, depend on support ships or platforms for their operations, including transport to and from dive sites. The Titan was a submersible that operated from the support ship Polar Prince, a former Canadian Coast Guard icebreaker. Both vessels cater to tourism, with submarines being popular in island locations like Hawai‘i and the Caribbean, while submersibles are typically found on expedition cruises.

What is the safety level of submersibles?

A review of the safety records for classified submersibles reveals they are significantly safer than both airplanes and automobiles in terms of fatal incidents.

According to a representative from Triton Submarines, a leading manufacturer of private submersibles, “Classed human-occupied vehicles have maintained an impeccable safety record for over 50 years. Worldwide, these classified submersibles carry more than a million divers annually and have done so for nearly four decades without any fatalities.”

The critical factor is that these submersibles are certified by independent classification societies. In contrast, OceanGate chose not to pursue certification for the Titan, claiming in a now-deleted blog post that the process would delay their innovations, which they viewed as detrimental.

Conversely, naval submarines have experienced several fatalities; the U.S. Navy has suffered the loss of thousands of submariners, primarily due to combat rather than accidents, though incidents have occurred. The Navy has significantly enhanced submarine safety with the SUBSAFE quality assurance program, initiated in 1968, which has greatly decreased major incidents since its inception.

What regulatory measures are in place for the submarine and submersible industry?

In terms of legal oversight, there is very little—no international regulations govern the operation of submarines and submersibles. However, operators usually take it upon themselves to ensure their vessels are certified for safety, which is often necessary for obtaining insurance. “Naval submarines receive certification from the Navy, while private submarines are certified through private channels,” explains Margarethe.

Private certifications are managed by various third-party classification societies worldwide, such as DNV and Lloyd’s Register. If you’re considering a submersible tour, it’s crucial to verify that your vessel is classified by a reputable society. “Certification involves a rigorous, time-intensive, and thorough independent evaluation of every facet of a human-occupied craft’s design, production, and operation,” notes the spokesperson from Triton. This process assesses everything from material choices to operational systems and includes a dive to the maximum operating depth.

Certification isn’t a one-time event; it continues throughout the submersible's operational life. “While inspection intervals vary slightly among different certification agencies, all require annual evaluations,” says the Triton representative. “Each year, the classification society inspects the hull, structural integrity, safety systems, life support equipment, and the operation of mechanical, fluid, and electrical systems.” Additionally, Triton subs undergo more comprehensive assessments at longer intervals, with class renewals occurring every five years.

What are your rescue options in case of an emergency?

Submersibles are equipped with multiple systems to ensure they can surface; if one mechanism fails, another will activate. For instance, many submersibles have a ‘drop weight’ at the bottom that maintains balance but can be released to allow the sub to ascend.

In cases where a sub becomes stranded at the ocean floor, most will be at depths that allow for undersea rescue, whether via divers or another submersible. “On the submarine I operated, we never took passengers below 150 feet for safety reasons. This ensures that, in an emergency, vents accessible to divers could fill our ballast with compressed air and elevate the submarine,” explains Margarethe. In contrast, the Titan was diving to a depth of 12,500 feet, the site of the Titanic wreck.

However, the diving location is crucial to consider. Several new expedition vessels carry submersibles that can operate in isolated and often hazardous areas, such as Antarctica. In these remote settings, rescue operations may be significantly more challenging due to the time it may take for rescue teams to reach the site or factors like sea ice.

Is a submersible tour worth it?

Submersible tours provide a unique view of the ocean that most people never experience. As long as the operator follows proper safety measures like classification and regular inspections, these tours are a safe way to observe various marine life. However, there's always some risk involved, especially in remote areas, so it's a personal decision you'll need to make.

There are definitely advantages to underwater tourism. “Having a tour guide enhances your experience, offering insights about what you're seeing and helping you connect with the ocean,” Margarethe shares. “It’s crucial to nurture a connection with the water, as it covers most of our planet and urgently needs our care and attention.”

My first submarine experience was during a family vacation to the U.S. Virgin Islands as a child; we went aboard an Atlantis Submarine. While I didn’t focus much on the technical aspects, I vividly remember being captivated not just by the vibrant sea life around us, but also by how the water alters color perception as you descend. Atlantis subs accommodate several dozen passengers who can gaze out through long viewports. The size of the sub—or perhaps my small stature at the time—made it feel quite spacious, alleviating any claustrophobic feelings.

Last year, I enjoyed my second dive, this time in Antarctica. The luxury expedition ship Scenic Eclipse features a submersible called Scenic Neptune, which holds six passengers and a pilot. The passengers are seated in two expansive acrylic spheres offering 280-degree views. Although this sub was much smaller than the Atlantis vessel, the spheres created a sense of openness. The only moment that felt a bit claustrophobic was navigating through the narrow hatch and descending the ladder.

The marine life in Antarctica is, naturally, very different from what you would encounter in the Caribbean. Understanding that this underwater realm is rarely seen by “ordinary” individuals like myself, I was utterly fascinated by all forms of life, from tiny krill to enormous sea sponges. I did feel a bit anxious about the dive, having experienced how unpredictable conditions can be in Antarctica on a previous trip. I was concerned something might go awry. However, my 45-minute dive went smoothly, although Scenic Neptune experienced an incident in November 2022; a strong weather event known as katabatic winds caused ice floes to move over the sub, causing minor damage and keeping guests underwater for a couple of hours. Fortunately, all passengers and crew made it back to the ship safely.

Key questions to ask your tour operator

If you’re apprehensive about booking a submersible tour, here are some inquiries you can make to your operator to alleviate your concerns.

Is the submersible classified, and by which organization?

Certification by a third party is an essential safety protocol in the private submersible industry.

How frequently do you conduct inspections on the submersible?

Submersibles should undergo inspection after every dive.

What is the maximum depth the sub can reach, and how deep will our dive be?

Most submarine tour operators avoid diving to the maximum depths of their subs—which is a wise precaution. Better safe than sorry.

In case of an emergency, how long can the sub remain submerged?

Inquire about the oxygen supply onboard, as well as the provisions for food and water.

If the sub becomes immobilized on the seafloor, what rescue procedures are in place?

Tour operators should confidently address this question, as they ought to have multiple safety protocols established.

Does the submersible possess an emergency beacon to transmit our location during a crisis?

Most submarine tour operators will have a surface support vessel to closely monitor the sub. However, it is advisable for the sub to be equipped with an emergency position-indicating radio beacon (EPIRB) or a submarine emergency position-indicating radio beacon (SEPIRB) on board, both of which will relay the sub’s location during an emergency (the former operates on the surface, while the latter functions underwater).