| After boiling it again, he measured the decay of the resulting radon gas with a gold leaf electroscope. |
| Active devices detect and record radon or its daughter products continuously. |
| These can be found through the detection of gases such as sulphur dioxide, hydrogen sulphide, and vapours of mercury, iodine, and radon. |
| The ground in some parts of the country releases radon, a radioactive gas that can cause cancer. |
| Another problem, discussed here, is that the first daughter product of Ra is radon gas. |
| The radon gas will then also decay into radioactive solid particles, called radon daughters or radon progenitors. |
