An electrical device would have to be totally sealed against sea-water.
Alex couldn't see exactly what was happening but he guessed that the room really was like a bottle, totally sealed apart from a hole somewhere above.
At the very bottom of the rampart, and totally sealed by it, was a small hearth.
Few Now Pass The border now is not totally sealed.
The room had sealed totally and airlessly.
Since buildings are not totally sealed (at the very minimum, there is always a ground level entrance), the stack effect will cause air infiltration.
I thought that the suit had to be totally sealed.
The room must be totally stable, and totally sealed.
The units are totally sealed to protect the worms from any bugs.
It was totally sealed, totally dark, and icily cold.