Radon is a gas that occurs naturally in the earth’s crust. It is invisible, it is odourless, and it is tasteless. Radon is a product of the decay of uranium. When uranium decays, it turns into lead. This is a 14-step process; radon is formed at the sixth step.

Carbon Monoxide

Carbon monoxide is a colourless, odorless gas. It is a by-product of incomplete combustion, such as natural gas, liquid fuels, and anything that burns.