Radon is a naturally occurring radioactive noble gas that is colorless, tasteless, and odorless.
Radon enters indoor spaces through cracks in the joints between concrete floors, walls, gaps in the floor, small holes in hollow-core wall blocks, and through cesspools and sewers. As a result, radon levels are typically higher in basements, cellars, or other structural areas in contact with soil.

The primary health risk associated with high exposure to radon is an increased risk of lung cancer. Scientists are also investigating whether radon levels found in homes and other locations pose significant health risks. These studies have now been completed, and a meta-analysis of key research projects in Europe, North America, and China has confirmed that radon in homes significantly contributes to lung cancer worldwide. According to recent estimates, 6–15% of lung cancer cases are caused by radon.
Some households obtain their drinking water from groundwater sources (springs, wells, and drilled wells). Groundwater often flows through rocks containing natural uranium and radium, which produce radon. This is why water from deep wells typically has higher radon concentrations than surface water from rivers, lakes, and streams.

There are several methods to address radon in the home that can reduce radon levels in indoor air, including sealing cracks in floors and walls and increasing ventilation in the building. There are five main ways to reduce radon accumulation in a home:

• Improve ventilation in the home and prevent radon from entering living spaces from the basement
• Enhance underfloor ventilation
• Install a radon collection system in the basement
• Seal cracks in floors and walls
• install a positive-pressure or forced-air ventilation system

By Michael Chiu, MWS, CI
Previously published in Ming Pao Daily News