Direct answer
What does Radon mean?
A naturally occurring radioactive gas that can enter buildings from the ground and cannot be seen or smelled.
Exam cue: Testing is the way to determine a building's radon level. Do not infer safety from location or building age alone.
What does it look like in a question?
New York example
A buyer uses a qualified test to measure radon before deciding whether mitigation is needed.
Common exam trap
What should you not confuse it with?
Radon is a gas, not a visible mold or an asbestos fiber.
Related construction and environment terms
AsbestosA group of mineral fibers formerly used in many building materials and associated with health risks when fibers become airborne and are inhaled.Environmental assessment formA New York SEQRA form used by an agency to help evaluate the environmental significance of a proposed action.Environmental impact statementA detailed document examining potentially significant environmental impacts, mitigation and reasonable alternatives under SEQRA.FoundationThe part of a structure that transfers building loads to the soil or supporting material below.Lead-based paintPaint containing lead that can create serious health hazards, especially for children, when it deteriorates or creates contaminated dust.Load-bearing wallA wall that carries structural load from above in addition to its own weight.
Sources used2 references with section locators
The curriculum citation confirms exam scope. Definition and rule citations support the explanation itself. Links and locators were checked on August 26, 2026.
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