Assertion: radon | /r/HasProperty | created
Facets:
value: constantly
type: TEMPORAL
value: from the decay of radioactive elements
type: CAUSE
Source sentences:
text: Radon is created from the decay of radioactive elements that naturally occur in rocks and stones in the soil.
text: Radon is constantly generated and available to enter and accumulate in buildings at high concentrations.
text: Radon is created when radium, element #88, breaks down through radioactive decay.