How One Choice Opened the Door to the Diverse World of Nuclear Safety – Pasi Junninen’s Career Path to Licensing and Safety Manager at Platom 

Sometimes a career path is built on carefully planned steps – other times it begins by chance with the right choice. For Pasi, that happened in 2004 when his studies at Lappeenranta University of Technology had reached the thesis stage. Among three different thesis opportunities, the one related to nuclear power felt like the right fit, even though nuclear technology was unfamiliar territory. The choice turned out to be the right one – and the very first step into the world of nuclear safety. 

First Steps in a Career: Apros and an Interest in Process Modeling and Simulation

Pasi’s master’s thesis focused on modeling the PKL test facility using the Apros software and analyzing the experiments. The work was carried out as a collaboration between the Radiation and Nuclear Safety Authority (STUK) and VTT – with workdays spent at VTT, where the core of Apros development was and where he received the best possible support for using the software. When he graduated as a Master of Science in Engineering in the summer of 2005 – already 20 years ago – it was a natural step to continue at VTT as a researcher.

Process modelling swept me away, but Helsinki and Espoo never felt like home to an eastern Finnish country boy like me.
When my fellow student Harri Kiiski tipped me off about Platom’s great work atmosphere, I decided to give it a try. The year was 2008 – and Platom became the place where my career truly took off. 

From Expert to Team Leader 

For years, Pasi focused on Apros modeling and analytics—until 2017 marked a turning point. He moved to the Hanhikivi project to support the plant supplier and took responsibility for developing the PSAR (Preliminary Safety Analysis Report), especially Chapter 15 (Transient and Accident Analyses). Leading an international team was a new challenge—and an important step from expert to manager. 

Earlier, in 2015, Pasi had been appointed head of Platom’s process modeling team, but the Hanhikivi project deepened his understanding of leadership in a demanding environment. The path progressed logically: step by step toward more challenging and meaningful responsibilities. 

Trust and Lessons from Crises 

One of the highlights of Pasi’s career came in 2021 when he was elected as Platom’s employee representative on the board—with an overwhelming majority of votes. It was a clear sign of trust and a memorable moment, especially since the other candidates were also exceptionally strong. 

But working life isn’t only about victories. The collapse of the Hanhikivi project wiped out a large portion of the company’s revenue almost overnight. Pasi describes that time as the greatest learning experience of his career—a moment when realism, calmness, and hope were the most important compass. 

I hope that at that point I was able to make my small contribution to the position we hold in the industry today. It was essential to keep a cool head and stick to an optimistic mindset based on strategy—the situation had to be clarified, and future opportunities examined. 

Optimism must not be unfounded, but on the other hand, pessimism doesn’t move things forward. It’s about having a clear picture of the situation and seeing the possibilities, Pasi sums up the challenging period. 

The Present and the Future 

Currently, Pasi leads Platom’s safety and licensing team while still working on demanding expert tasks related to both operating and new nuclear power plants. In his role as team leader, he is also part of Platom’s operations management group. 

Motivation comes from the fact that every project brings something new to learn, so the work never becomes monotonous. At Platom, collaboration within the team and the management group works well—we support each other. Expert tasks involve deep technical problem-solving, while team leadership focuses on working with people. This combination keeps the work diverse and meaningful. 

Every task should be done as well as possible—otherwise, there’s no point in doing it at all, Pasi states. 

The future goal is clear: to continue on the same path. Step by step, at his own pace, toward increasingly challenging responsibilities. Platom provides an excellent environment for progressing at the right speed. 

Balance for work life from the summer cottage and forestry work

In his free time, Pasi finds balance through a variety of physical activities: gym workouts, running, cycling, and in winter, skiing and downhill skiing. Time spent at the summer cottage —fishing and clearing the forest—offers the perfect counterbalance to work in front of a screen. Best of all, these moments are shared with family. Walking with Lapphund Nala is also a great way to unwind and get the heart rate up. 

A good balance between work and leisure has supported Pasi’s career all the way to Platom’s board, as an expert and team leader—sometimes it’s important to lose yourself in a summer evening by the lake, fishing rod in hand, recharging your batteries. 

“Fishing has actually been useful at work too—because in 2024 I won an ice fishing competition during Platom’s recreation day. Oh, and I also won a shooting contest, but let’s not talk about that”, Pasi laughs.