The full paper is under review Abstract: An emissions baseline for a city is the foundation to building an informed clean air action plan. This includes an understanding of the sources and their intensities to device cost-effective measures with the least health impacts. In an urban environment, emissions from road transport is one of the major contributors to the air pollution problem, and accounting for this sector requires a detailed profile of in-use vehicles, covering their age-mix, usage, and fuel economy. In this paper, we present a simplified framework to survey at select fuel stations to establish the necessary inputs and use them to build a localized vehicle emissions inventory. The methodology is illustrated with an application in the city of Patna, India. Here, the FuSS was employed to profile the in-use passenger vehicle characteristics by 19 trained students, over nine days and at ten fuel stations, to collect 9,775 survey points. The methodology outlined in this paper, along with the tools and training framework, is also replicable in settings other than the fuel stations. Files includes here are: A copy of paper survey forms A presentation showing the survey locations and their surroundings A copy of the ODK survey form This is a sample form - ODK-Sample-VehUsageSurveyPatna.xlsx Use xls2xform (python library) to convert this into xml format to upload to ODK A presentation of walk-through the app screenshots (used for training purposes) A copy of the excel-based emission calculation tools (more @ https://urbanemissions.info/tools) All the geospatial (GIS) information for Patna (and other Indian cities) is available@ https://urbanemissions.info/india-air-quality/india-ncap-cities/