What is the objective of a sub-slab or sub-membrane depressurization system?

The objective of a sub-slab or sub-membrane depressurization system is to create a vacuum beneath the foundation of a building. This system is designed to prevent radon gas from entering the living spaces of a home by establishing a negative pressure area underneath the slab or membrane. When the vacuum is generated, it effectively draws radon gas from the soil into a piping system that safely vents it outside of the home, thus reducing the concentration of radon indoors.

The mechanism relies on the principle that air will flow from areas of higher pressure to lower pressure, and by maintaining lower pressure beneath the building, radon and other soil gases are kept from infiltrating the indoor air environment. This approach is a fundamental aspect of radon mitigation strategies, aimed specifically at minimizing exposure to radon gas, which can pose health risks including lung cancer.

Creating a vacuum also helps to disrupt the pathways through which radon could otherwise enter, thereby enhancing the effectiveness of the radon reduction system. This is why establishing that negative pressure beneath the foundation is critical for controlling radon levels in homes.