'Each section can be sealed by air-tight doors,' Dealey said.

In extensive tunnelling systems, air-tight doors were introduced to control air flows.

Daniel slammed down his faceshield; some of the air-tight doors had dropped into place but others were jammed in their tracks.

No phone cord would go through the air-tight door.

Once packed tightly inside (to minimize available air), the steel air-tight doors were closed.

The air-tight door to our bunk room slid across automatically and settled into its gaskets and we were locked in.

For a wild moment Conway fought the urge to run to the air-tight doors and beat on them with his fists.

The air-tight door slid aside, hesitated as the still-hot section moved into its recess, then came fully open with a rush.

The corridor outside was empty but I banged on the air-tight door and they let me through to where the rest were waiting.

In case of accident, an air-tight door would snap shut across the opening, sealing the ship into separate compartments.