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An ear for success

Photo: Nacre
Photo: Nacre

The idea of an intelligent earplug was conceived over a cup of coffee. Today, this special hearing protection unit is the best of its type in the world.

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It is 1989, and at SINTEF’s Department of Acoustics, research scientist Odd Kr. Pettersen is struggling over a letter. A Danish company wonders whether Norwegian acoustics scientists can solve the noise problems experienced by workers in an Italian factory.

“We can offer hearing protection based on a lightweight headset…” writes Pettersen, and hesitates over his next phrase, “…but we also have access to new technology in the field of mini-loudspeakers and integrated circuits which means that we could develop an intelligent earplug – a little device that could be inserted directly into the auditory canal.”

For some years, acoustics scientists at NTH (the Norwegian Institute of Technology, one of NTNU’s predecessors) and SINTEF, led by Professor Asbjørn Krokstad, had been carrying out a wide-ranging research programme on hearing and hearing aids. Everyone realized that the field had a great deal of potential, but the route from there to an actual product was something that no one had even dared to think about.

Now, for the first time, researchers had turned vague ideas into words on a sheet of paper, and the task of developing an intelligent earplug was under way.

With them all the way

Almost 25 years later, Pettersen sits with his colleague Jarle Svean and tries to summarize the years of work to develop and industrialize their ideas. They have passed through a process that they will never forget, but now they can harvest the fruits of their efforts.

Svean goes into the adjoining office and comes back with what looks a little snail shell in his hands: “This is what the earplug looked like in 1992. It’s nothing special. In the 1990s, the concept of damping sound with “anti-sound” was already known, but what was unique was putting the principle into an earplug.” “Today, QUIETPRO is the best product of its kind in the world,” says Pettersen thoughtfully. “Everyone who needs to communicate under extremely noisy conditions knows about us. It’s funny to think about it.”

The Swedes arrive

Throughout the nineties, the department struggled to finance its project. Chief scientist Aage Thunem worked hard on an industrialization programme and made strenuous efforts to find industry partners who would dare to participate in the effort. Time after time, companies would indicate their interest, contracts would begin to take shape, but then the whole thing would fizzle out.

The scientists had always thought of their hearing protector as something for heavy industry, and in 1996 an opportunity suddenly turned up. The Norwegian Ministry of Defence had purchased a number of tanks from the Swedish company Hägglunds. Now the Swedes had a counter-purchase contract to fulfil, and they needed to find a project in Norway. They had heard about the Norwegian invention, so they contacted SINTEF and said that they were interested.

In 2000, SINTEF revived a dormant company called Nacre, which had long existed only on paper. The idea was that it would be easier for an industrial partner to cooperate with an existing company than with SINTEF as a large organization.

At the same time, SINTEF invested NOK 5 million in its own company, and the Norwegian and Swedish defence forces contributed a further MNOK 23.7. This was the turning point: at last, the project was underway. Soon afterwards, the Viking Venture fund also put money into the project.

Under development

All this time, the earplug had been under development. What had started out as pure hearing protection now began to take shape as a communication system: a microphone picked up the sound of the user’s own voice in the auditory canal – from the interior of the head, as it were. This meant that his or her voice was not distorted by ambient noise and could be transmitted to other people. The user himself was protected from noise and at the same time could hold a conversation in very noisy surroundings.

The next few years saw a lot of testing and hard work. It was a difficult time, with much stress and sleepless nights. In April 2003, just as the scientists were about to leave for the Easter holiday, they discovered a software error in the system. This was depressing, but they rolled up their sleeves and tried to fix the problem.

Late in the afternoon, one of them gave in and rang home to his family to let them know that there was not going to be much of a vacation that year. He spent the rest of Easter in the lab, which meant that the demonstration set up for a few days after the break could be held as planned.

Even at the Christmas party in 2004, teamwork took precedence over fun and games. At the Department of Acoustics, coffee and cakes were brought down to the cellar, but while their colleagues sat at table singing Christmas songs, the team was still working at full steam in the laboratory.

The way ahead

From 2006 onwards, however, just about everything began to go according to plan. Nacre won an order worth more than NOK 200 million to supply QUIETPRO to the US Marines. This was the definitive commercial breakthrough for the technology company. In autumn 2006, the company was put on the market, and in the following June, Nacre was sold to the French/American company Sperian for NOK 750 million.

The earplug is still winning new markets: For the past four years, the Norwegian oil company Statoil has been collaborating closely with Nacre and SINTEF on the development of a new civilian version of the system. Offshore platform workers are exposed to extremely high noise levels, putting them at risk of losing their hearing completely, and Statoil wants the earplug to be adapted to offshore applications.

In the summer of 2010, the partners presented QUIETPRO Offshore, a specialized earplug that measures the amount of noise that individual operatives are exposed to and gives them a warning signal when the upper threshold of acceptability is reached and they need to leave the area. This will give Statoil a quite unique overview of the noise load of each of its platform workers. According to the company, the system represents a complete paradigm shift in terms of protecting employees from injurious noise levels.

Today, Nacre has 20 employees, two of whom are located in the USA. Although the company has been sold, it is still located in Trondheim, and collaborates closely with NTNU and SINTEF.

Jarl Svean and Odd Kr. Pettersen know that their earplug is the best product of its type in the world. They also realize that they have run a race they will never forget.

Åse Dragland

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