Measuring key emission parameters of VOC from materials based on concentration trajectory in ventilated chamber

Volatile organic compounds (VOCs) emitted from materials in indoor and vehicle environment is one of the main factors causing poor air quality and obviously affects people's comfort and health. The emission behaviors of VOC from materials are characterized by three key parameters, i.e., the initial emittable concentration (C₀), the diffusion coefficient (D_m) and the partition coefficient (K). Determination of the above key parameters is the foundation of researches for emission laws of VOC from materials as well as prediction for human exposure and health risks. Based on the most widely used VOC emission process in ventilated chamber at present, this paper proposes a novel method to simultaneously determine C₀ and D_m. By assuming an initial value for K and then performing the linear curving fitting for the logarithm of chamber concentration, the key parameters C₀ and D_m can be obtained from the slope and intercept of the fitting results. As is shown in sensitivity analysis, the variety of K has little effect on the determination of C₀ and D_m. By the virtue of the treatment for experimental data of ventilated chamber tests in literature, it is demonstrated that the proposed method has a relatively high accuracy.