Concrete removal and rock breaking made easier. Dexpan® is a non-explosive demolition powder with 18,000-psi expansive strength when mixed with water. The slurry is poured into pre-drilled holes (1.5-inches diameter recommended) Dexpan® breaks concrete and rocks safely, and quietly. Not recommended for projects less than 6-inches in depth. Small cracks can begin to appear as early as 12 hours, but waiting for 24, 36, or 48 hours will result in more extensive and wider cracks. Non-toxic material(Calcium Oxide).