Entering a Wreck

By John Adsit PADI MSDT and Trimix Instructor 190645

I watched from the back of the dive boat in South Florida as the divemaster came back on board after setting a descent line to a wreck and began his dive briefing. He described some areas, especially the wheelhouse, where there are nice swim-throughs “for those who have the proper certification.” I knew the DM to be a highly experienced technical diving instructor, and I recognized his careful wording. Before I splashed for the dive, I quietly asked him what that proper certification might be. He smiled. We both knew that there really was no certification that allowed people to make the short, simple swim from one side of the wheel house to the other. As far as either of us knew, such a journey was strictly forbidden by all the major agencies.

That was the dilemma that dive operations and many others around the world face. They know their customers are going to go through those simple overhead environments. They know that if they forbid them from doing so, the customers would simply patronize another operation. It is the same with famous dive sites like Cozumel. A dive operation that refused to take divers through the famed swim-throughs there would be out of business in no time. Yet, they do that believing there is no language in almost any agency, particularly PADI, that allows it.

That exchange led to a lengthy email exchange with PADI in 2017, an exchange in which I was told that I misunderstood their policies and procedures for entering not only wrecks but natural overhead environments as well. Those entries, I was told, are indeed allowed. I countered that the wording in their course manuals, including the wreck diving course, said just the opposite, and I provided the quotations. They recognized the problem and asked me to suggest alternative wording. When I provided it, they asked permission to use it in the future.

The future is now. In the third quarter 2018 issue of their professional journal, the Undersea Journal, PADI published my wording, so that suggested alternative language is now officially in place.

This article will both quote that language and expand upon it in describing the kinds of decisions a diver makes when entering a wreck. If it seems to contradict much of what you have believed to be true, then that makes my original point about the deceptiveness of the original language. According to PADI, what follows in this article has always been their policy, so there is nothing new here. It is just alternative language. It should be viewed as supplementary to a full recreational wreck diving course rather than a comprehensive treatise on entering a wreck, for it does not include detailed descriptions of the kinds of hazards associated with these environments.

Two Kinds of Entries

The current PADI wreck course defines only one kind of entry, which they call penetration. Because the course does not actually define the term, readers will naturally use the common dictionary definition and assume it refers to all entries. In reality, though, penetrations by their definition are rarely done in recreational wreck diving. The most common entries (swim-throughs) are not even mentioned in the 2 course. When the PADI wreck diving course talks about “penetrating” a wreck, it is not talking about swim-throughs. Swim-throughs are not considered to be penetrations, and they are not currently mentioned in the course at all.

Here are the new definitions of the two terms as they are found in the Undersea Journal.

In a swim-through, the diver enters through one opening and exits through another. In a basic swim-through, the diver will always be able to see two exit points to open water using natural light. The path between them will be free of significant obstacles, entanglements or silt. The combination of the distance to an exit point and up to the surface should not exceed 40 metres/130 feet for Advanced Open Water Divers and higher, and in other circumstances the distance should be the depth for which the diver is qualified.

In a penetration, the diver enters more than a few metres/feet into the wreck intending to return to the entry point, either because there is no other exit or the diver is not sure there is another one. The diver may go beyond the point that the entry is still clearly visible and must run a line to ensure a safe return to the exit. The path should be well lit and free of obstacles, entanglements or silt. As with swim-throughs, the distance to the exit and then to the surface should not exceed 40 metres/130 feet.

A swim-through is by far the most common kind of entry in recreational diving. Even the most avid recreational divers may complete hundreds of wreck dives without seeing more than a few penetrations outside of a class environment—if that. The purpose of a swim-through is to enter in one point, exit at another, and then continue to explore the wreck without returning to the original entry point. If that is the goal, laying line would be counterproductive, since the diver must retrace that route to pick up the line before the dive is over. A swim-through can be as simple as cutting a corner of a deck by a few feet while circling the wreck, or it might be a much more complex trip requiring advance planning and technical diving skills.

Penetrations are relatively rare, and they require more skill for even the most basic penetration. Laying line effectively takes more skill than it first appears, and taking that line back up, surprisingly enough, can take even more skill, especially when working in current. Line being retrieved can easily become entangled, and that can cause a dangerous delay in the exit. Divers who intend to penetrate wrecks using line and reel should get plenty of practice in open situations before trying it in a wreck where their lives depend upon it.

The Importance of Sound Judgment

From the first OW training dive to the last dive of a lifetime, divers have to make sound judgments. They have to evaluate the conditions of a planned dive and determine whether their training, skills, experience, and equipment are suited to those conditions. That especially includes overhead environments. PADI’s language regarding overhead environments is curiously lacking in this regard, and most existing statements can be summarized as don’t do it! Ever! In truth, though, PADI believes some overhead environments are really just part of open water, and even beginning divers can safely navigate some of them. In fact, a training bulletin years ago confirmed that short swim-throughs can under some circumstances be part of an OW training dive. 

Many PADI courses tell divers that they should always dive “within the limits of their experience and training.” What PADI made clear to me in our discussions that this means that as a divers training and (with “and” also meaning “or”) experience grows, so does the diver’s ability to extend limits. For open water divers, that means that they can gradually dive deeper and deeper after they complete their open water training. For wreck divers, that means they can expand beyond the limits imposed by the definitions of swim-throughs and penetrations as defined above.

Divers considering entering a wreck need to make those judgments, and an important part of a good wreck course is understanding what kinds of dangers may be present so that divers can make better judgments. A dive that would be too dangerous for some divers might be completed with relative ease by others.

In making sound judgments on wrecks, divers should be governed by two important qualities: patience and humility. As divers’ skills grow, they will be handle more and more difficult environments. They need to have the patience to let those skills grow and not rush headlong into a situation for which they are not yet prepared. Humility is the quality that allows them to recognize and, most importantly, accept that their skills are not yet where they need to be.

This can be a challenge for divers who have learned to excel at a certain basic level of diving, thereby developing justifiable pride in their abilities. They may not realize how unprepared they are for an environment demanding skills they have not even seen, let alone mastered. In such an environment, the real problem for divers is that they cannot know what they do not know. If they have not been trained to dive in that environment, they will not know what dangers lurk and what skills are required.

Let’s look at a two dive teams diving a very large wreck that was prepared and sunk to make a dive site to see how they can use sound judgment in making plans to enter a wreck. They have both completed the wreck specialty, and they both have the deep diver specialty as well, meaning they feel comfortable diving to a combined depth and linear distance of 40 meters/130 feet.

One team checks out a door on the upper deck, at a depth of about 90 feet. They see a room with another door across from them, with light coming through it, indicating more openings to the sea beyond it. There are a couple small obstacles in the room, which they can easily bypass. Only a thin layer of gray silt lies on the floor. To the side they see a large, square hole, sufficient for two divers to pass at the same time, which was cut in the hull as part of the preparation for making this a dive site. If they enter the room, they will never be more than about 15 feet away from that hole to the open water, so they are within the total depth and entry distance consistent with their certification.

They feel confident and enter the room. They will treat this as a swim-through, so they do not lay any line. They swim across the room and peek through the other door, where they see another room just like the one they are in. If they enter it, they will be close to another hole in the hull, so they would not be adding any more distance to the surface. They enter it. They see another door and check it out. Before long they have gone through the length of that deck, doing one basic swim through after another, and they were never too far from an exit to the surface.

Meanwhile, the other dive team has gone to a lower deck and found another doorway. When they look in, they see the beginning of a maze of passageways. It gets dark past the first room. There is no serious silt, and there are no obstacles. With no sign of another exit in sight, this is no swim-through, so if they 4 want to enter, they must lay line. Their depth is already about 100 feet, so they will not be going far before they reach their allowed distance. More importantly, they are only diving with aluminum 80 tanks, and they wonder if they will have the ability to run line, turn, and retrieve the line before they are low on air and have to ascend. They decide that this penetration will have to wait for another day, a day when they are better prepared for it.

Going Beyond Basic

The definitions for swim-throughs and penetrations both refer to their most basic levels, and judgment is required when conditions go beyond basic. As more challenging conditions begin to appear, they are no longer basic, and divers must use determine if their skills and equipment are advanced enough for those conditions. For example, a layer of dark, fine silt could create a nightmare siltout for a diver whose buoyancy and kicking skills are not advanced, but it might not be a serious concern for a certified cave diver. Recreational divers who want to enter wrecks regularly and make more advanced entries should invest in the training needed to master buoyancy, horizontal trim, and non-silting kicking techniques.

Equipment is an important factor for divers going beyond basic as well. Anyone who has ever followed a buddy through even low-silt swim-throughs while that buddy is flutter kicking with free diving fins will attest to the benefits of being able to use a frog kick with appropriate fins. Using the long hose and bungeed alternate regulator typically used by technical divers means buddy teams can exit through smaller openings in an emergency. Powerful lights like those associated with cave diving can make up for lack of natural light.

As conditions become more complex, the growing dangers demand further training. Wrecks not prepared to be dive sites include hanging wires and other potential entrapments. As wrecks rust, walls begin to collapse. Some wrecks are filled with deep, dark, loose silt that can completely destroy visibility when disturbed. Many wrecks are at depths that call for decompression training. Divers should get advanced wreck training before entering wrecks that go that far beyond the basics.

In all cases, the most important asset in going beyond the basics is sound judgment. Sound judgment comes from having the ability to assess your own skills objectively, the humility to accept a true evaluation of your skills, and the patience to be able to wait until you are truly ready.