INVENTOR FROM BANJA LUKA TAKES THE WORLD BY STORM

Speleodiving, one of the most dangerous disciplines in underwater exploration, often puts divers in life-threatening situations where a lack of air can be fatal. But a groundbreaking invention by Banja Luka-based innovator and diving instructor Zoran Dujaković may soon change that.

Dujaković has developed an underwater gas and liquid refueling device, which has won gold medals at innovation expos across the globe. His invention allows divers to safely refill their air tanks while still submerged—an advancement that could save countless lives.

Recently, Dujaković was awarded the Master of Innovation title for the second time by the International Organization for the Promotion of Innovations (OFID). This is just one of many accolades that confirm his status as one of the most prominent inventors from the Republic of Srpska.

“While speleodiving, I realized how dangerous it is when you can’t surface and must return through tight underwater tunnels. If you run out of air, the result is often fatal. That’s when the idea came to me—to create a device that lets you refill your tank underwater,” said Dujaković in an interview with Glas Srpske. He sketched out the concept, built a prototype, and tested it in a pool and in the depths of the Vrbas River.

His device includes hoses, a compressor, a special refill valve, and another valve attached to the diver. A unique feature of the invention is a system that prevents water from entering the tank, making underwater refueling just as safe and effective as on the surface.

Beyond diving, the device can also be used to transfer chemicals from sunken tankers without risking environmental pollution, making it both a safety and ecological breakthrough.

However, like many innovators, Dujaković faces financial hurdles.

“There’s little interest in innovation funding in our region. Foreign companies are ready to buy the finished product, but I lack the resources to mass-produce thousands of units to make it profitable,” he explained. His current plan is to self-finance the production of a few hundred units and offer them to diving centers worldwide.

Dujaković’s passion for innovation began in his youth. He co-founded the Speleology and Diving Club Gremlini, and to afford ropes and gear, he and a friend cleaned windows and worked at heights. This led to their first invention—a mobile scaffold for working at any height.

“I won a silver medal for that in Banja Luka. I was overjoyed and proudly showed it off to guests during my family’s religious celebration. Later, the same invention earned several gold medals at international exhibitions,” he said.

The scaffold is still in use today, and Dujaković is in negotiations with a Chinese company that may produce it commercially.

One of his most cherished honors is being named an academic of the Serbian Academy of Inventors and Scientists, where he was the youngest member among esteemed scientists.

Dujaković’s achievements include five gold medals in the U.S., and more recently, two golds from expos in Australia and Japan. Another of his notable creations is a universal, ultra-light orthopedic immobilizer—an alternative to plaster casts. This breathable and shower-friendly device was developed over ten years ago. Though similar technology has since emerged in New Zealand using 3D printing, Dujaković takes pride in being one of the concept's pioneers.

“I went to the U.S., then Afghanistan, and the project was paused. Later, I saw a university in New Zealand had developed the idea using 3D tech that didn’t exist when I first created mine. I may not be the one to commercialize it, but it will surely reach the market,” he reflected.

To young inventors, Dujaković offers this advice: “Don’t give up, even when it’s hard. Innovation is an expensive but rewarding hobby. The key is to believe in your ideas and use modern technology to bring them to life.”

Over the years, Zoran has traveled to more than 40 countries, both for business and tourism. One of his most unique experiences came during his time working in Afghanistan.

“I worked as an explosive detection dog handler. I went abroad in search of better opportunities. Even during that time, I created an invention that received recognition at innovation fairs, and in some cases, even won the grand prize,” Dujaković concluded.