In 1995, the Virginia Department of Transportation (VDOT) adoptedthe ignition method as an alternative to chlorinated solvent extractionfor quality control and acceptance of hot-mix asphalt. The productionof trichloroethane was outlawed in the United States on December31, 1995, as part of the 1990 Clean Air Act Amendments.

Implementation of the ignition method was accomplished througha training program jointly sponsored by VDOT and the industry.Approximately 75% of the industry began using the method in 1995.

Field data from four standard VDOT mixes were evaluated. Themixes were produced at different plants and contained differenttypes of aggregate from different sources. Test data from theignition furnace, solvent extraction, and nuclear asphalt contentsare provided.

As a result of VDOT's favorable experience with the ignitionmethod, this method is mandatory for all VDOT QC/QA.