What are VOC’s? VOC’s (volatile organic compounds) are typically derived from solvents, dry cleaning fluids, fuels, and by-products of chlorination, and may include chemicals such as carbon tetrachloride, tetrachloroethene (PCE), trichlroroethene (TCE), methytlene chloride, benzene, and methyl tert-butyl ether (MTBE). Common sources include existing or discontinued underground storage tanks, dry cleaning operations, gas stations, and industrial processes.
Vapor Intrusion occurs whennegative air pressure inside a home or building draws volatile organic compound (VOC) vapors up into the structure from underlying soil and water. These chemicals can sometimes travel underground from one property to another, and then enter through drains, cracks, crawlspaces, control joints, sumps, and utility penetrations, creating a potential health risk for occupants who inhale them.
Health Risk Health risks include cancer, organ toxicity, or reproductive effects. No concentration of these chemicals may be considered healthy. Gases, such as methane from landfills, also present potential explosive hazards, requiring special treatment.
Vapor Mitigation Systems Cascade Radon’s engineering techniques used in radon mitigation translate perfectly to resolving VOC concerns. Sub-soil and sub-membrane depressurization are the most common and effective means of reducing soil-borne VOC contamination, creating negative pressure in the soil beneath a building with a fan-driven vent system, which then exhausts the vapors to above the roofline. Installations may involve sealing of vapor entry points such as drains, sumps, cracks, and crawlspaces.
Mitigation may also include changes or adjustments to existing HVAC systems. VOC mitigation systems can also reduce the effects of other soil contaminates such as radon gas, and generally improve overall indoor air quality.