Assertion: radon | /r/CapableOf | build up to dangerous levels
Facets:
value: inside a house
type: LOCATION
Source sentences:
text: Radon can, however, build up to dangerous levels inside a house.
text: Once there, radon sometimes becomes trapped and builds to dangerous levels.
text: Radon can, however, build up to dangerous levels inside a house, any other buildings, or caves.