Sometimes people pose questions about the "symptoms of radon gas". This is a tricky question to answer, because it's unclear what the person is really asking.
Why?
Because, taken literally, the question doesn't mean anything. Radon gas does not have symptoms. Simple enough, right.
But perhaps the person means to ask: how do I know there's radon gas in my home? This is a sensible question, but also a scary one. The answer is that unless you measure radon gas levels, you don't know. Radon gas is colourless and odourless; that's why it's dangerous.
However, the person could also mean: what symptoms would I have if I came into contact with radon gas? To which the answer is also simple and more than a little scary. You wouldn't have any symptoms. You wouldn't get a rash, for example, and you wouldn't start to sneeze.
Hopefully, that covers whatever the person asking that question actually wants to know.