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Kategorie: ‘Fagerstrand’

Becoming a Commercial Diver at NYD

April 30th, 2025 | by
  • Maschinenbau B.Sc.
  • Norway, Fagerstrand
  • NYD (Norsk Yrkesdykkerskole)
  • 11/2024 – 03/2025

Diving has been a life long passion of mine and thanks to Erasmus+ I had the chance to combine it with my studies in mechanical engineering to go to Norway for four months to become a Commercial Diver at NYD (Norsk Yrkesdykkerskole).

I got to spend a beautiful winter across the Fjord from Oslo in a small town called Fagerstrand filled with around sixty upcoming and eager divers from all around Scandinavia and the world.

The first two weeks were the basic theoretical foundation for diving: physics, medicine, first aid, seamanship, usage of diving equipment, fire hazards, decompression tables and pressure related effects of breathing gases. Everyday we learned about new subjects and gathered in groups to study and work on the assignments.

©Andreas Pietzcker

Before we could start diving we had to pass a medical check, fitness tests and a chamber dive to 50 meters to test our nitrogen tolerance. Breathing nitrogen at high pressures leads to the so called Nitrogen Narcosis or „Rapture of the Deep“. Usually the symptons set in at 30m and feel a bit like being drunk. The narcosis gets stronger the deeper you go (divers call this the Martini effect), so naturally at 50 meters we were in quite a cheerful mood. The air felt viscous due to the high pressure, you felt the high breathing resistance and most notably it changed your voice, making all of us sound like Donald Duck.

So naturally we sat in the cramped chamber bursting with laughter.

The first day of diving was filled with excitment. New equipment, check lists, for a few of us the first time they would ever get to experience the feeling of weightlessness underwater. I had been diving since I was twelve but this was a whole different world for me. Our equipment weighed in at around 30 kilos and we were glad when we climbed down the ladder into the water and could finally float.

Then we practized our bouyancy, an essential skill, to maintain a neutral position and neither sink nor ascent to the surface uncontrolled. We learned how to rescue an unconscious diver and bring him back safely, how to operate the winch to heave him out of the water and get him on a stretcher to perform first aid.

©Andreas Pietzcker

We were diving from Buldra, a dynamic positioning vessel (DPV) which uses it’s thrusters to maintain a fixed position in the water with pinpoint accuracy allowing divers to work safely. After a week of familiarizing ourselves with the equipment we took Buldra out to sea and dove from the wet bell. The wet bell uses the same principle as the first diving bells; it creates an air pocket within the bell with an open bottom, which allows divers to leave and return. In case of equipment failure the air pocket is our safe haven. During these dives we performed several inspection tasks on the bell, checking for example the electrical connections or the shakles used to attach the bell to the guide wires. The deepest dive with the wet bell was to 27m.

The next two weeks we learned about diving from the dry/closed bell and the transfer under pressure. The difference between the wet bell and the dry bell is, that on the dry bell we have a hatch which allows us to seal the bell on the bottom and maintain the bottom pressure while the bell is going up to the surface, whereas the wet bell’s pressure is always equal to the surrounding pressure.

The advantage is that the divers can be safely transferred under pressure (TUP) to a surface chamber, where they can decompress. The closed bell is used for deeper dives and saturation diving. On the station our worktask was to assemble different pipes using flanges to build a simulated distribution block for oil.

We learned about rigging and operating whinches. Underwater we guided them into place by making fine adjustments with a chain hoist and carefully positioning each part. We made sure the connection would not leak by using rubber gaskets and then screwed the pieces together using bolts. Especially important for making a good connection was the proper tightening of the bolts, where we did several passes tightening them little by little and always crosswise to make sure the pipes were properly connected.

©Andreas Pietzcker

Then we learned the use of lifting bags. Our goal was to lift a steel structure weighing about one metric ton. To figure out the weight we dove and took measurements of all the H-beams that make up the steel table. We worked out a total weight of nearly 950kg.

To prevent an uncontrolled ascent of the load we first rigged the table to a so called dead-mans-anchor. If we would fill the lifting bag to its total capacity the load would rise to the surface uncontrolled, where the bag would turn over, dump the air and come crashing down onto the divers. The dead mans anchor prevents this. This is just one example of the many things we learned about proper rigging, how to connect shackles and make sure they are loaded properly.

We filled the lifting bag and when we saw to table beginning to rise we could lift it with our bare hands and move it along the seabed.

We were also working on the pillars that make up the pier. We constructed a wooden frame underwater to be able to pour concrete. For the frame we cut 2×4 wood pieces into the correct length and profile of the bottom. To install rebar we used a pneumatic rock hammer drill to drill into the granite seabed. One diver operated the drill and the other diver guided the tip of the drillbit using a so called “Sea mans wife”. The drill we used uses around 60 liters of air per second. Which meant a whole lot of bubbles for us which made it rather difficult to see where we were drilling.

© Andreas Pietzcker

We learned how to use the AH3 and AH5 (air hat) free flow helmets. Their design is based on the old diving helmets like the Siebe Gorman whose history stretches back over a century. The difference of a free flow helmet is that there is a constant supply of air to the diver instead of a demand system, where air is supplied only when the diver breathes.

The helmet is connected to the dry suit and excess air has to be dumped with a valve that can be operated by pushing it with the side of your head. Again we were working on the concrete pillars, excavating and cleaning away the surrounding seabed to expose the bedrock. For cleaning we used an air lift which sucks away material using a difference in pressure and high and low pressure water jets as well as shovels to move material.

At around 15m there was an old steel tank which had been encrusted with barnacles and other types of sea life. We cleaned the tank using a hydraulic brush and got it nice and shiny again. As you would have expected of a group of guys, while we cleaned the surface we used parts of it for our own artistic expression.

We continued with deep dives up to 50 meters which also is the maximum depth a diver can work at breathing air because of the toxic effects of nitrogen and oxygen at these high pressures. We also did surface decompression. After deep and long dives the body builds up nitrogen which has to be released slowly or bubbles form in the divers blood which can have fatal consequences. To avoid this divers do decompression stops, which can be impractical because of long times in freezing water or waves. Surface Decompression works by lifting the diver quickly out of the water and recompressing them to a depth of 15m where they start breathing pure oxygen. To avoid bubbles from forming this has to happen quickly, within five minutes.

One of the most exciting things to learn about was underwater wet welding. Using specially made electrodes we practiced fillet welds and T-joints. Underwater welding is very different from welding on land, because the weld cools extremely quickly and has a tendency to crack if one works to fast. After joining a lot of steel plates together it was time to take them apart again by oxy-arc cutting. And electrode is ignited and supplied with a steady stream of oxygen which enables and exothermic reaction so that the tip of the electrode burns at around 5000 degrees celsius. This made short work of the steel plates which melted away like butter. It was an incredible experience to stand less than half a meter away from this bubbling and glowing metal next to a stream of smaller and sometimes larger explosions if a pocket of hydrogen gas had formed.

© Andreas Pietzcker

Lastly we trained on using Scuba gear and the Interspiro mask. This is the equipment used mostly by firemen and rescue divers and we practiced search patterns for lost objects (we had a chain and, of course, a gun), rescuing an unconscious diver, did inspection dives and cleaned the hull of the dive vessel Buldra, where we had started to dive all the way back in November.

It sounds crazy but diving into freezing water with equipment that weighs nearly as much as you do, is an amazing and fun experience. It is truly something extraordinary, the feeling of floating weightlessly in the water or walking with lead boots along the seabed like the astronauts on the moon.

Diving is a team effort and I was priviledged to work with some amazing, caring and professional individuals during this four month stay. We grew together as a group and took care of each other.

Every day there were new challenges and new things to learn and new experiences, so every morning I was glad to go there. And in the evenings we met, cooked and laughed together, watched movies, had barbeques or went out to Oslo to party.

There are so many different aspects to diving that it is hard to put into words but in essence it is a gateway to a truly unique world where adventures await. I will never forget the time I spent in Norway nor the lessons that I have learned and I am hoping that this will just be the beginning of an incredible journey. I want to thank Erasmus for giving me this opportunity and I will cherish these memories for a long time.