Assertion: ventilation shaft | /r/HasProperty | vertical passages
Facets:
value: in subterranean civil engineering
type: OTHER
Source sentences:
text: In subterranean civil engineering, ventilation shafts, also known as airshafts or vent shafts, are vertical passages used in mines and tunnels to move fresh air underground, and to remove stale air.
text: In subterranean civil engineering, ventilation shafts, also known as airshafts or vent shafts, are vertical passages used in mines and tunnels to move fresh air underground, and to remove stale air.