Volatile organic compounds (VOCs) are carbon-containing chemicals that evaporate at room temperature, originating from paints, solvents, adhesives, furnishings, and cleaning products. Common indoor VOCs include formaldehyde, benzene, toluene, and xylene. These compounds degrade indoor air quality and trigger respiratory irritation, headaches, and allergic reactions, particularly in sensitive populations.
Sources and Concentrations
Building materials, furniture, carpets, and office equipment emit VOCs through off-gassing processes lasting weeks to years. Indoor VOC concentrations typically range from 100 to 500 micrograms per cubic meter, though new construction or renovations can exceed 1,000 micrograms per cubic meter. The WHO recommends keeping cumulative VOC levels below 200 micrograms per cubic meter.
Control and Reduction Strategies
Source control through low-VOC or zero-VOC product selection prevents emissions at the source. Increased ventilation with outdoor air exchange rates above 15 cubic feet per minute per person effectively dilutes VOCs. Activated carbon filters and photocatalytic oxidation devices remove VOC molecules from conditioned air. Allowing new furniture and materials to off-gas in well-ventilated areas before occupancy reduces peak indoor concentrations.