The Japanese are renowned for developing some of the most innovative gadgets and new technologies in the world.

Now one company has developed a new type of smoke alarm for deaf people.

It uses the pungent smell of wasabi, a common ingredient in sushi.

Roland Buerk reports from Tokyo.

Transcript

Roland Buerk: Anyone who has eaten sushi will know all about the flavour it can have - a very mustardy, peppery, horseradish. That's caused by this green paste inside, it's called wasabi. If you have too much wasabi it can get right up your nose and make your eyes water. Wasabi is made by grinding down a very pungent root. And it was perhaps while eating in a restaurant like this one the researcher came up with an idea about what this beloved ingredient in Japanese food could be used for.

And this is what they came up with. What it is is a smoke alarm for the deaf, for people who wouldn't be able to hear the noise of a normal alarm. This one detects smoke, it emits a stream, a jet of extract of wasabi. We'll give it a go.

(Presses button on fire alarm)

(Alarm makes siren sound and emits wasabi extract)

Roland Buerk: Now, it really is a very strong, horseradishy, almost garlicy smell that catches your nose and the back of your throat. Chigusa Shimokawa is from the company that has developed this product. We're awake and we can smell it strongly, but if you were asleep would it wake you up?

Chigusa Shimokawa: Yes of course.

Roland Buerk: How quickly does it wake you up? Because that's crucial in a fire isn't it - how quickly you get out of the burning building?

Chigusa Shimokawa: Most people will wake up within one or two minutes.

Roland Buerk: In the course of developing this product, they tried lots of different smells - banana, this one is coconut milk, this is tea tree oil - that's a pretty strong smell too. But in the end they found the best odour for waking people up was a humble wasabi root.