Radon is a naturally occurring radioactive gas produced by the breakdown of uranium in soil and rock. It can enter buildings through foundation cracks, floor joints, and service penetrations. Because it is odourless, colourless, and invisible, it often goes undetected until it becomes a significant health concern. According to Health Canada, radon exposure is the leading cause of lung cancer among non-smokers and contributes to more than 3,000 deaths in Canada each year. While every building has some level of radon, sustained exposure to elevated concentrations is the concern, and that risk can only be managed through consistent measurement.