The incenerated municipal soild waste (MSW), after further processing, can be used as fines in bituminous mixes. Processing is done to remove ferrous and nonferrous metals and to achieve the required particle size gradation. Due to the presence of larger fraction of fines, MSW ash is primarily used as fine aggregate. It is also used as a fill material in road construction. The ash can also be stabilized with portland cement or lime to produce stabilized base/sub-base material (TFHRC 2004).

For conventional road materials, a number of tests are conducted and their acceptability is decided based on the test results and the specifications. This ensures the desirable level of performance of the chosen material, in terms of its permeability, volume stability, strength, hardness, toughness, fatigue, durability, shape,viscosity, specific gravity, purity, safety, temperature susceptibility etc., whichever are applicable.

There are a large number tests suggested by various guidelines/ specifications. Figure-6 presents a suggested flow chart to evaluate the suitability of industrial waste for potential usage in highway construction.

Health and safety considerations should be given due importance handing industrial waste materials ( Mroueh and Wahlström 2002, Nunes et al. 1996).