We usually don't drink from fountain unless

来源: 2013-11-05 17:17:21 [旧帖] [给我悄悄话] 本文已被阅读:

we run out of water we carried.

We don't know when was the fountain filter was changed. In my company, all fountain (and coffee machine) filters are changed every 3 months. But in public area, I don't know when the filter was changed.