A silent alarm system to warn deaf or hard of hearing people of a fire, using the pungent smell of Japanese green horseradish, was developed in collaboration by Seems Inc. of Tokyo, Air Water Safety Service Inc. of Kobe, and Shiga University of Medical Science.
Assistant Professor Makoto Imai of our Psychiatry Dept. conducted a clinical test.
A total of 14 subjects in their 20s to 40s, including 4 deaf people with hearing loss were tested.
After an electroencephalogram showed that a subject was asleep, at first a non-smell-fire smoke was sprayed in the small examination room to confirm that the subject maintained sleep.
One and half minutes after, real wasabi smoke was sprayed in the same manner.
Except for one person with a blocked nose, all 13 others awoke and pressed the response button in 10 seconds to 2 minutes after the smell reached them.
According to the results of this test, it was judged that the wasabi smoke has an awakening property and the wasabi fire alarm is effective, especially for the people with hearing disabilities.
The news concerning the world’s first fire alarm system with “wasabi”-smell received coverage in Japan-wide news by NHK on March 2, 2008. It was also distributed to the world by Reuters and the BBC, leading to favorable responses.