Concentration characteristics of ozone and product for indoor occupant surface chemical reaction under displacement ventilation

Indoor chemical reaction occurring between ozone (O3) and occupant surfaces (skin, hair, and clothing) is an important source of volatile organic compounds (VOCs) in the indoor air. This kind of chemical reaction can bring obvious impact on indoor air quality (IAQ) and building occupant health. Theoretical model describing indoor occupant surface chemical reaction between O3 and Squalene, heat and mass transfer was established and verified by indoor environment experiment in this present study. Meanwhile, in order to obtain variation characteristics of ozone and product concentration in typical indoor space, four kinds of factors were taken into account and their influence on occupant surface chemical reaction under displacement ventilation was analyzed by means of numerical simulation, including air exchange rate (ACH), ozone concentration in supplied air, squalene concentration on occupant surface, chemical reaction rate. The results show that the rising of ACH is one favorite method for reducing the exposure concentration of product (secondary pollutant) under displacement ventilation. Moreover, as to ventilation system design and its commissioning, it's very necessary to reduce ozone concentration in supplied air by reasonable measures. In addition, lower squalene concentration on occupant surface and chemical reaction rate are very meaningful for improving IAQ during ventilation process.