All subway stations in Korea have gas masks.

In Korea, You can see gas masks all over the subway stations. I don't knore whether or not other countries are the same. About 5~7years ago, There was a disaster in a subway of Deogu which is number three city of Korea. Many people had been killed by harmful gasses after that maybe safety gas masks were equipped in all subway stations.

However I think it is insufficient as a provision for fire because women have no idea how to use exactly. For men in Korea, it could be very useful in a state of emergency. All males have to serve in a military where we can get used to using gas masks.