Never use or run a generator indoors, or even near areas that could allow exhaust gas to enter your home or shelter. This is serious stuff, PEOPLE DIE EVERY TIME THERE IS A NATURAL DISASTER. Living in hurricane alley, I sadly know this all too well. We need very strong warnings required on all generators. I would even be for a proper operation and placement certification program to be run by local disaster organizations.
I hate to read about the needless deaths caused by unsafe generator use every time there is a blackout, but it happens every time. Safe generator operation and placement is a matter of life and death. It doesn't take hours or days, it can kill in mere minutes.