Specifications include, but are not limited to: Highway noise is always a top environmental concern with the public on any highway project. The Reference Energy Mean Emission Level (REMEL) database is an inventory of different vehicle pass-by noise levels that is the basis for the Federal Highway Administration (FHWA) Traffic Noise Model (TNM) analysis software. It is 25 years old and in need of updating due to changing vehicle fleet characteristics. Newer noise measurement technology has also evolved, and it can be applied to locate and quantify noise generators on a moving vehicle. The REMEL database directly affects noise impact and mitigation analyses on federal-aid projects. Research is needed to update the highway noise dataset using existing and new highway acoustic measurement technologies to account for the change in the vehicle fleet. OBJECTIVE The objective of this research is to update the REMEL noise database to account for new vehicle fleet with focus on Newer passenger car (PC) types, Medium truck (MT), Heavy truck (HT), and Electronic vehicle (EV). At a minimum, the research team should use three acoustic measurement technologies (beamforming, wayside sound level, and on-board sound intensity [OBSI]) that will better quantify the position and distribution of vehicle noise sub-sources: mechanical, exhaust, tire/pavement, and aerodynamic sources.
