Category — Line protocol

I just finished a cave course with three guys from Guadalajara. After the whole swine flu disaster and flights canceling it was cool to be back in my normal day to day routine. The group consisted of Hector, Oscar and Juan David being the students and Santiago assisting to move a step closer on becoming a cave instructor. The three guys had previous experience in technical diving and all the necessary equipment which gave them a good head start.

On the first day we met in Pro Tec and started of with a little introduction and a bit of theory. We spoke about the course, equipment, communication and the value of proper trim and buoyancy. After that we put the gear together and configured it cave diving style just before we took of to Cenote Xtabay. Once we arrived there we started with training the basic positions for the different fining techniques. The best way to do that in my opinion is to lay flat on a table with your fins on. Afterwards we went down to the waters edge only with our masks and fins to train the techniques in water but without the double tanks. It is way easier to focus on what your legs, ankles and feet have to do without having to think about neutral buoyancy in the same time. After about an hour we went to get the rest of our gear and submerged to try all of the propulsion techniques in full equipment. Of course nobody was perfect after that session but we made an important step towards being able to maintain position in one spot which is necessary to maintain visual contact with the guideline, the cave and the rest of the team at ALL times.

All in all it was a very long but very productive day that we finished at about 7pm.

On the next day,we changed a couple of things on the equipment and configuration that we had figured out the day before while practicing and then quickly loaded the truck to make our way towards Cenote Cristalino.

There we started with basic line drills in between the trees namely how to lay line and how to follow it in zero visibility. First we trained independently, and later as a team.

Juan David, Hector and Oscar training zero visibility exit

 After the lunch brake we geared up and started with a review of the fining techniques of the day before. I used the time and placed a line circuit in the open water area of the Cenote that we would use to train different skills, drills and techniques to prepare ourselves as good as we can before moving into the overhead environment. We spend hours going around the circuit training emergency drills, zero visibility and focusing on team diving and clear communication. It also became apparent to everyone how task loading can result into stress and the stress blocking clear and proper problem solution thinking.

The team training touch contact; Santiago taking notes

The next day we were set and ready to go cave diving. First location was Jardin Del Eden aka Ponderosa but before we entered the water we quickly reviewed line protocol and line laying when multiple teams are involved.

Once in the water we worked ourselves through bubble checks, gear matching, dive briefing and setting limits for the dive. After that we dropped down and started our dive with s-drills. I lead the first dive to demonstrate the use of the reel with the light and how to secure tie offs and route the line.

On the second dive already Oscar was the team leader and so the three headed of into the inky darkness. As expected mistakes where made and so we used the time left after the second dive to stay in the water and continue to train our “basic skills” such as buoyancy, trim and propulsion.

The next day we came back to ponderosa to do longer cave dives including emergency drills on the exit portion of the dive. We did a total of three dives that day including a zero visibility exit, an out of air scenario and switching donor while exiting as well as an out of air drill that was followed by zero visibility. All of the above we had successfully trained in the open water before and now it was time to use the learned in a simulated emergency in the cave.

The Team Training Touch Contact U/W

That evening we continued on with some theory and the decision that Hector would stop at the Introductory Cave Level to built up experience and confidence before moving up to the cave diver level. He spent the next days finishing his Intro course with Nando and later going on some awesome guided dives.

I continued the next day with Oscar and Juan David in Taj Maha. We started in the parking lot to discuss lost line and lost diver procedures and protocols before we jumped in the water for two cave dives including many different drills such as light failure, out of air drill, zero visibility, lost diver, lost line amongst others. Because the two where exceptionally skilled we even started with navigation on the second dive involving one jump.

The next day we returned to Taj Maha but this time instead of diving downstream like the day before we dove upstream to incorporate restrictions and some more navigation in our training. Of course we continued with the usual out of air, zero visibility drills in every single dive. Coming back to Pro Tec we used the time in the evening to finish up on some more theory and talk about circuits and traverses before calling it a day.

Next morning we drove to Minotauro. It is not a usual site for me to visit during a course since the cave is smaller, fragile and definitely not suited for 99% of people that are still in or have recently finished their cave training. However the two guys where working hard the days before and with their previous technical diving experience had the necessary skills to dive there. We used the first dive to prepare the circuit and attempted to execute it on the second dive. That combined with some exercises made for a great day in the jungle and two awesome cave dives. By the smile on their faces it was easy to tell that the two had fallen in love with cave diving.

On the last day of the course we decided to drive all the way to Tulum to see the difference between the caves that are further north and the caves in the south of the Riviera Maya. We decided to do two dives towards the Cuza Nah Loop. On one dive I would be with them and the other one they would do by themselves to verify that everything that they had learned in the past days was working as well without an instructor watching their every move.

It was a great day and the perfect finish for a cool course. On the way back we stopped in Tulum to get some ice cream which is simply a tradition that can’t be broken!

The last day before they left, we all, including Hector with Nando did a last dive in Nohoch Nah Chich. Oscar, Juan David and I made our way downstream while Hector and Nando decided to the dive the upstream section. It was a fantastic day with insane weather and due to the swine flu situation almost no people which created a wonderful silence around the Cenote.

All in all a great 9 days with a genuine nice group of people, lovely weather and the breathtaking beauty of the caverns and caves here in the Riviera Maya.

Guidelines are the life lines within water filled caves. As long the visibility is good all is good and our vision will guide us toward the exit of the cave. It is when we lose all visibility that we are in need of the guideline to lead the way out of the cave, back to the surface and to ambient air. One of the leading causes of fatalities and near tragedies in cave diving involves the failure to follow a continuous guide line. This can occur when divers penetrate a cave without running a line from openwater to the permanent guideline or transfer from one line to another without installing a gap or jump line. To insure maximum safety, each segment of the dive should have a line installed that allows divers to follow it in total darkness. In addition, lines in a cave should be marked by directional arrows, personal non-directional markers such as “cookies” or cloth pin markers to indicate the exit path.

Permanent Lines

Permanent lines are installed permanently within a cave system. Their purpose is to facilitate the diving and exploration of a cave system and to insure a properly installed guide line is available for all visiting cave divers to use.

The permanent line installed in the cave system is often referred to as a main line, permanent line or a traverse line. The permanent line begins as close as possible to the cave exit but is at time cut back into the cave to avoid open water divers finding the line and going on cave diving. This line continues down the main passage to a specified termination point. The permanent line usually begins at some point beyond the cavern zone of a cave. A primary reel is used to travel to this line.

Navigation in Caves

In many caves there are more than one permanent line in that particular part of the cave making it a necessity to navigate inside the cave along the permanent lines where permanent intersections can be bound, referred to as a “T“. When a diver wishes to dive from one line to the next and is physically moving over to the other line this is referred to as a jump as long as leaving the end of one line going to the middle of another, leaving the middle of one line going to the end of another or leaving from the middle of one line and going to the middle of another. Leaving the end of one line and going to the end of another is referred to as a gap.

The exit has to be marked properly installing line arrows or personal line markers in order to secure that the exit has been marked and identified in a way it can be clearly understood in zero visibility and under high stress. It must be assured at all times that a continuous guideline is installed all the way to the openwater area of the cave entrance.

Gap and / or Jump Lines

A gap or jump line is one that is placed in passages that lead off from the primary line. Usually this line is placed as close to the permanent line as possible, but sometimes as far away as 30 feet / 9 meters. At the junction where a gap / jump line is installed, line markers such as directional or non-directional should be installed indicating and marking our exit point.

Line Techniques

Skillful use of reels and the proper placement of lines is essential for efficient cave diving. The primary reel should always be tied off with a primary tie off at a point in open water where direct ascent to the surface is possible. This may be accomplished by beginning the line just in open water, providing the location allows divers to descend directly to the surface. There are numerous viewpoints on the merits of where to place the starting point but it must be initiated at a point that allows direct ascent to the surface.

Within and just inside the cavern zone, another safety tie off must be made called the secondary tie off. Should the primary tie off come loose the second one should keep the line in place close to the surface. If possible the secondary tie off could be done around 15 – 20 feet / 4.5 – 6 meters depth, to aid and indicate safety and decompression stop depth in zero visibility.

When a line is being laid, tension must be placed on the reel to avoid “backlash” and protect the reel from jamming. When entering a cavern or cave and another team is exiting, yield the right of way as the exiting team has the right of way so they can leave easily.

A safety tie-off or placement must be made when a change in direction in the cave system occurs. Special care must be taken to avoid line traps. A line trap occurs when the line is allowed to be placed in an area where a diver cannot maintain physical contact with it during silt out. Ideally, the line should be placed in close proximity to the cave floor so divers can swim above it.

Line protocol requires awareness of the locations of the lines at all times. Always avoid swimming underneath the line. It may become tangled in your equipment or manifold. When crossing a line where your body will be in close proximity, use the reverse side of your open hand to keep the line away from your body. Do not grip or tug on the line while swimming. The proper hand contact to use is the “OK” sign. That is, form your fingers into an “O” and place them around the line. In silty areas keep in contact with both your buddy and your line. If a line becomes damaged, take the time to make repairs. This precaution may save your life. Avoid excessive wraps. Each time a line wraps over itself the structural strength is weakened considerably.

If an exiting cave diving team is encountered the exiting team has the right of way since they are low on air and on the last stretch of their cave diving journey. The only proper procedure to use one guideline in-between two teams is to discuss this procedure before the dive with all divers seeing the reel to be used and a personal marker to be used. The first team is installing the reel and continues the dive while the second team in is marking the exit side of the reel with a personal marker. The first team out is taking out only the line marker while the last team out is taking the reel out. If in any doubt if the other team already exited the reel and line must be left inside.

Line Markers

Line markers are used on guide lines to help you indicate directions in regards to where the exit is or to mark survey or science stations. Line markers are described as directional or non-directional markers. They consist of line arrows for directional line markers to clearly indicate the exit or direction to be taken toward the exit. Non-directional markers or personal markers are round “ cookies “ and clothespins used to mark locations or exits but have the advantage that they cannot cause potential confusion in regards to direction for other teams. Line arrows are triangle-shaped arrows with built-in slots to enable divers to attach them to the guide line. These are installed to indicate the direction of the nearest known exit. Often these will be marked with the distance from the cave entrance. Personal markers either directional or non-directional must be marked with your name or initials to identify them during the dive as reference points.

Line moving and removal

Guide lines installed in the cavern or cave area by other teams or permanent lines within the cave are not to be disturbed, touched, moved or removed by any individual. If lines are in the way for our own planned dive we may need to choose a different dive site. Our lines need to be placed in a way not to interfere with the other dive teams inside the cave as they do not know anything about the other lines close by. Our line needs to stay away from the other dive team’s line. We cannot use the same tie-off points as the other dive team’s line.

If lines need to be repaired or changed the proper procedure is to contact one of the cave safety officers who have been appointed by the training agencies to save guard the permanent lines installed within the caves. They will discuss the changes or repairs needed and will make them. After a repair or change is done the cave diving public will be informed about the changes or repairs. Many of the lines we see inside the caves are donated by training agencies and private individuals.