Air Water Safety Service, Inc. in Japan, you would have no worries. The "comforting" smell of wasabi would be sure to wake you up from your sleep.
The Apartment Therapy blog Unplggd has a story about this fire alarm. I had heard of it before but there's much more info in that blog post than I'd been aware of. Apparently it wakes almost everyone up within two and a half minutes! The smell of wasabi was formulated not to irritate the eyes, but just to make the sleeper aware of the smell. The actual chemical it outputs is allyl isothiocyanate, which is also present in horseradish.
The device costs $225 (down from $560). Unplgged has a great suggestion for use - not just for deaf people, it could also be used in loud venues like concerts and at sporting arenas. Though it might just confuse people at first.