Modeling is essential to the development of indoor chemistry as a field. Comprehensive, integrated physical-chemical models that include a realistic representation of how buildings influence indoor processes are needed to assess gaps in our understanding, to improve experimental design, to generate hypotheses for investigation, to guide measurements, and to indicate key species to quantify and the detection limits required for quantification. The MOdelling Consortium for Chemistry of Indoor Environments (MOCCIE) consists of six teams of investigators with expertise and models in six different areas: kinetic process modeling, gas-phase chemistry modeling, molecular dynamics simulations, modeling of indoor secondary organic aerosols and organic aerosols, computational fluid dynamics modeling, and modeling surface interactions and the role of clothing and textiles. MOCCIE has determined that the best way to ensure reproducible indoor chemical science would be to strive to construct a fully integrated open source model. This requires converting each of the six existing MOCCIE models into an open source format. Funds from this grant would support a project to convert Nicola Carslaw’s gas phase chemistry model into a fully open source platform using the Python programming language. Additional funds support the construction of a new user-friendly interface to facilitate the model’s use and production of supporting documentation.   In addition to the modeling work, Carslaw will work to expand science communications about indoor chemistry by engaging a U.K.-based freelance science journalist, Nina Notman. Notman will attend indoor chemistry events and conferences, and give a plenary on science communication at the 2018 Indoor Air Conference.