By Marcus Aronsson, Södra Älvsborg Fire & Rescue Service, Sweden
Becoming a rescue diver is about far more than learning how to dive.
It is about physical capacity, mental control and the ability to make the right decisions when both body and mind are under pressure and visibility is zero. It is about trusting your body, your equipment and the people on the surface when someone’s life may depend on the dive team succeeding.
For me, the journey began long before my first dive at Greater Stockholm Fire Brigade’s rescue diver school.
PREPARATION
It started with a decision. A decision by my employer to look beyond age and simple economics.
On paper, it is probably more cost-effective to send a 28-year-old firefighter on a rescue diver course, provided that person remains in the profession all the way to retirement. But younger firefighters can leave the profession after only a few years. Several have. I have a little over ten years left as a firefighter, and I know I am staying.
For me, the investment therefore made sense. Not despite my age, but with my age as part of the equation.
I had wanted to complete the rescue diver course for almost 15 years. Now there was also a clear operational need. We needed more rescue divers and future diving supervisors.
But the decision was not only about work. For me personally, that part was simple. I knew I could get myself into peak condition and prepare for the task.
The difficult part was something else.
My family.
My wife and our four children.
Two months away from home. Two months in which everything at home would have to work without me being there in the way I normally was. Driving children to activities, shopping, cooking, laundry and cleaning. Family life, basically.
I spent a few days building myself up to the conversation before finally asking my wife to sit down with me at the kitchen table. Then I told her.
At first she went quiet. Then she was happy for me. She knew how long I had been waiting for this.
It felt as if a weight had been lifted from my shoulders.
Now the real work began.
I knew I could not simply turn up for the course and hope my body would take care of the rest. Rescue diver training is not something you “get fit during”. You need to arrive prepared.
I did not just want to survive the course. I wanted to be able to develop during it. That was important to me. I wanted to focus on learning, improving and experiencing the course, rather than simply surviving from one day to the next.
That was why I chose to prepare properly.
It was not about becoming an elite athlete. Many different kinds of people have successfully completed the course over the years.
But I know myself. I know the level I expect from myself, and I know that I function best when my body is properly prepared for the task. Then I can be more present during training, absorb more of what I am being taught and deal with the physical load in a calmer way.
So the training was not about becoming the strongest or the fastest. It was about building a body that would hold up.
Strength. Mobility. Swimming. Cardiovascular fitness.
I trained to improve my VOâ‚‚ max, but also to cope with working underwater at a high heart rate, under heavy physical load and with very limited opportunities to simply stop and rest.
I also practised underwater exercises and worked on coping with rising COâ‚‚ levels. Not to push dangerous limits, but to understand how my body and mind reacted when discomfort arrived. When the urge to breathe increased. When the instinct was to stop, but the task still required control.
Preparation was also about something that becomes increasingly important as the years pass.
Recovery. Sleep. Nutrition. Consistency.
Understanding how the body reacts to physical stress and what it needs in order to perform again the following day.
At 49, you can still be strong, fit and highly capable. But you cannot neglect recovery indefinitely and expect there to be no consequences.
Once the course begins, there is no time to catch up. You quickly find out whether the preparation has been done or not.
I also tried to prepare for everything I could control. Ear problems. Colds. Muscle soreness. Sleep and recovery.
My bag was filled not only with equipment but with nasal spray, ear treatments, painkillers and almost anything else I thought might help keep me functioning throughout the course.
It might sound excessive.
For me, it was about removing as many unnecessary uncertainties as possible. Nothing avoidable was going to stop me.
And in many ways, it worked. If my ears started causing problems, I dealt with them immediately. If muscle soreness crept in, I focused on recovery. If I felt a cold coming, I tried to stop it developing into something worse.
But no matter how well you prepare, you cannot control everything.
Early training focused on equipment, technique, safety procedures and learning to function under pressure.
THE FIRST WEEKS: BASIC TRAINING
The first weeks were based at Lillsved Folk High School on Värmdö, outside Stockholm. Pool diving took place at the Amphibious Regiment at Berga and at Eriksdalsbadet swimming centre in Stockholm.
At the beginning, it was not about diving deep. It was about breaking down old behaviours and building new ones. Learning yourself. Learning the equipment. Everything started from the beginning.
Water-based physical training. Buoyancy control. Buddy lines. Emergency drills. Safety procedures.
On land, much of it looks simple. Underwater, everything changes. Fine motor skills deteriorate. The equipment is heavy. Every movement costs energy.
At the same time, you still have to work methodically and remain calm.
You quickly realise that rescue diving is not about simply being “comfortable in the water”. It is about functioning under pressure.
Alongside all the practical training, the theory continued constantly.
Diving medicine. Diving physics. Safety. Regulations.
Boyle’s law, Charles’s law, Henry’s law and Archimedes’ principle went from things remembered vaguely from school to something very real and practical underwater. How pressure affects the body. How gases behave at depth. What happens physiologically when the safety margins become small.
It was not simply about studying for an exam. It was about understanding why the safety procedures exist and what actually happens to the body when something goes wrong.
The further we progressed, the clearer it became how closely theory and practice are connected in rescue diving.
Every decision underwater is built on knowledge.
During the first few days, a huge amount of time was spent on equipment. Getting dressed. Buddy checks. Preparing the diving sets. Checking valves, cylinders, buoyancy equipment and line signals.
Then doing it again.
And again.
Checklists governed almost everything we did.
At first, it could feel excessive. Very quickly, you understood why. Safety depends on the same things being done in the same way every single time.
When something happens underwater, there is no room for hesitation or improvisation.
The response has to be instinctive.
We also began practising emergencies very early. Loss of air supply. Mask problems. Situations where problems had to be solved despite stress and limited visibility.
Many of those failures should almost never be able to happen because the pre-dive checks are so rigorous. But if they do happen, the response has to be immediate.
There is no pause button underwater.
For me, the basic training was physically demanding, but manageable. I had prepared well, and I could tell that the training I had done beforehand made a significant difference.
What took longer to adjust to was the pace and the sheer amount of new information. New equipment. New ways of working. New routines.
A lot of it was familiar from breathing apparatus work, particularly the approach to safety, procedures and remaining calm under pressure.
But underwater, you are more exposed. The darkness, the cold and the isolation feel different.
I have never been afraid of darkness or confined spaces. Even so, there were moments when I felt very alone down there in the cold water.
That was when I had to use the tools I already knew.
Focus on the task, not the emotions.
Become Marcus the firefighter.
Not Marcus the person.
Somewhere during those first weeks, I also began to understand what CITA ET CERTA actually means in practice.
Swiftly and safely does not mean rushing.
It means being so well prepared that the right decision and the right action come automatically, even when the body is tired and visibility is zero.
Fully equipped and ready to dive. Despite careful preparation, cold water and intense physical exertion would soon push my body beyond its limits.
SIPE
It happened in the middle of the course.
SIPE.
Swimming-Induced Pulmonary Edema.
Pulmonary oedema triggered by swimming or diving.
The thing I could not prepare for.
The thing I could not control.
By then, the class had found its rhythm. The days were beginning to merge into one another. Dives. Theory. Briefings. Physical training. Long days wearing equipment.
My body was adapting to the workload and my confidence was growing.
I had carried a clear picture in my head of how the course would unfold. If I could just get through the basic training phase, I thought the rest would flow from there.
I had trained hard before the course and felt well prepared, physically and mentally. The possibility that I might become injured or ill had hardly entered my mind.
The risks were out there.
Not inside me.
Perhaps that is fairly typical of people in professions like ours. You focus so much on the task in front of you that you almost forget that your own body has limits too.
Then it happened.
During a dive in cold water, my body was under heavy physical strain. There was no drama underwater. No panic.
But when I reached the surface, I coughed and tasted blood in my mouth. I coughed again and spat into the water.
Yes.
It was clearly blood.
That was when I realised something was wrong.
I ended up in hospital, underwent examinations and eventually received the diagnosis.
SIPE.
Pulmonary oedema associated with diving and intense physical exertion in cold water.
For many people, that would have been an obvious signal to stop.
My reaction was almost the opposite.
When doctors and instructors talked about putting my health first, I struggled even to process what they were saying. In my mind, everything was about getting back onto the course as quickly as possible.
I was so focused on completing the training that I almost could not understand what they meant when they said my health had to come first.
What do you mean, first?
We investigate this, and then I carry on diving.
That was more or less how I thought.
When I was told it could take more than a week to get another CT scan of my lungs, I became frustrated. When the doctor said the heart ultrasound might take even longer, it almost felt irrelevant to me.
I wanted to get back to the course.
I pushed to have the examinations brought forward. I called. Asked. Pushed. Explained how much the course meant to me and that I needed the examinations before I could continue.
At the same time, it was a powerful reminder of how complex the body becomes under this kind of stress.
I had prepared carefully. Trained hard. Been in good physical condition.
And still, cold water, intense physical exertion and the right combination of circumstances were enough for my body to say no.
It created respect.
Not fear.
Respect.
For the environment.
For physiology.
And for how narrow the margins can sometimes be.
After the examinations, I travelled back to Stockholm on the Monday. On the way there, I received clearance to start diving again.
BACK AFTER SIPE
Once the diving restriction was lifted, there was really only one thought in my head.
I was going back.
I would catch up on what I had missed and step straight back in where the rest of the class was.
No gentle return.
No excuses.
For my first dive back, we were practising an ascent using surface-supplied air. The maximum ascent rate was nine metres per minute from a depth of around 18 metres.
The ascent chain hung alongside the boat and, objectively, everything was fairly controlled.
Inside me, it was anything but calm.
Returning to the water after SIPE became as much a mental challenge as a physical one.
I had decided that I was going to show everyone that I was ready again. That my body could handle it. That SIPE had only been a temporary interruption.
On the outside, I looked completely calm.
Inside, the adrenaline and cortisol were through the roof.
It felt as though they were spraying out of my ears.
The instructors saw it immediately.
I thought I was hiding it.
I rolled over the side and descended straight down the chain.
23 metres.
I was supposed to stop at 18.0.
Then back towards the surface. Perhaps a little too fast. Down again. Up again. Down once more.
Then finally back up, with a decompression stop on the way.
As I hung there breathing and waiting, the thoughts began to come.
What had just happened?
Why had I lost control?
Me, who thought I had control.
Me, who was going to prove myself.
For the first time, the thought seriously entered my head:
Maybe diving is not for me after all.
That evening, I took the time to talk to the instructors. They saw straight through me.
The stress.
The pressure I was putting on myself.
The need to prove something.
Then they gave me a piece of advice that has stayed with me ever since.
If you are stressed before the dive, you take that stress underwater with you.
Then the spiral begins.
Small mistakes above the surface become bigger below it.
So whatever you are about to do:
Breathe out.
Focus.
Calm down.
One task at a time.
That became something I carried with me for the rest of the course.
And quite quickly, I returned to the same level as the rest of the class. Deep dives. Search exercises. Long days in equipment.
Dive by dive, my confidence returned.
I had never really doubted that my body would hold up.
But I needed to rebuild trust in myself.
And somewhere in that process, I learned something important.
Physical capacity is not about being indestructible.
It is about understanding your limits, respecting the load and giving yourself the conditions you need to perform when it really matters.
Part 2: Depth, darkness and becoming a rescue diver will follow.
Comments
No comments yet — be the first!