Assertion: duct | /r/HasProperty | internal obstacles
Facets:
Source sentences:
text: Openings are within reach, covers require little effort to remove, the ducts themselves can support the weight of a person and are wide enough in diameter to allow an adult to pass through, there are no internal obstacles except for the occasional Deadly Rotary Fan blocking the branching corridors, they are free of normal sheet metal's dangerously sharp edges, they are totally soundproof, there are no security cameras, and there's never a lack of light or chance of getting lost unless the plot calls for it.