Elsa
I guess that depends on what you mean by "safe." To me it seems like a death trap if there's a fire or an earthquake or a tornado or whatever other disasters your area is prone to.
Being able to find your tamper evident emergency key, break it open, open locks, and remove them, in the dark, while still waking up, choking on smoke, and with very little time to spare, doesn't seem like something a person should have to be able to do to stay alive.
I try not to judge anything other people do consensually, but I sure hope they think through the risks.