Two reasons. One quite practical, in dense populations the mask reduces the grit that surrounds dense traffic along with industrial junk. Another is social custom as I witnessed in Japan during winter months. In Japan many n the streets might mask but in eating/drinking places the masks came off.
Two reasons. One quite practical, in dense populations the mask reduces the grit that surrounds dense traffic along with industrial junk. Another is social custom as I witnessed in Japan during winter months. In Japan many n the streets might mask but in eating/drinking places the masks came off.
Two reasons. One quite practical, in dense populations the mask reduces the grit that surrounds dense traffic along with industrial junk. Another is social custom as I witnessed in Japan during winter months. In Japan many n the streets might mask but in eating/drinking places the masks came off.