Abstract
The purpose of this study was to determine if sound could be used as a defining parameter to distinguish vehicles using studded tires from all other vehicle types. Vehicle sound data were collected using a sound meter device during the winter and summer seasons along a two-lane rural highway (State Highway 8) and a divided multi-lane highway (US-95) near Moscow, Idaho. The study examined variables including vehicle type, season, travel lane, and highway type. Based on the results, the study concluded that while vehicles with studded tires generated a higher decibel range that most passenger vehicles without studded tires, the range could not be differentiated from many pick-up trucks and semi-trucks with louder engine noises. While the results suggest that data collection methods using sound would require a secondary source such as video or a field observer in order to definitively identify vehicles with studded tires, an approximation method based on estimating the number of vehicles and the percentage of vehicles with studded tires produced results that were comparable to previously established methods.