Emissions Reductions Associated with the Use of Warm-Mix Asphalt as Compared to Hot-Mix Asphalt

This report presents results from a literature review and field testing that were conducted with the main objective of developing guidance for documenting the reduction in emissions associated with the use of warm-mix asphalt (WMA) as compared to conventional hot-mix asphalt (HMA). The literature review presents current methods for estimating emissions during asphalt production, current protocols to measure and control emissions, and case studies where WMA emissions were measured and compared to HMA. Field testing was conducted during asphalt paving at two locations where a given mixture was placed as HMA and WMA. Workers exposures to asphalt emissions were measured at each test site for both HMA and WMA. Data from both the literature and field testing provide averaged emissions reductions that range up to 70% for plant emissions and up to 50% for asphalt emissions during placement. The original document contains color images.