Beauty of Tatami - flame resistance
A tatami is hard to burn, and it takes more time to the fire to spread that even if an earthquake or a fire happen, you can escape in the meantime.
Tatami floor is made by compressed straw.
The reasons for flame resisting are this compression effect and hygroscopic character which keeps the proper degree of water inside.
In general, even if it catches fire, it gets only burned.
It is not to flare up at a stretch even if it burn.
In addition, it is made of straw and rush grass which are natural material that it won’t aerogenic poisonous gases such as carbon monoxide.
It is a common story that incombustibility of a tatami is recognized at the Fire Defense Agency, and on burnt a tatami in spite of misbehavior of smoking in bed.
(Of cause we always have to be cautious of fire prevention.)