Abstract: A method for safely removing even a hazardous contaminant from a substrate surface without either precoating the contaminant or constantly flowing an inert gas thereover is disclosed. A pulsed source of light energy having an output spectrum including an infrared component and a visible component is directed upon the contaminant. The directed energy being sufficient in magnitude to carbonize or to decompose the contaminant. Preferably produced by a flashtube, the energy has a repetition rate ranging from about 0.1 to 12 pulses/second, and a peak energy per pulse exceeding about 3,700 Joules. The sound and/or sound level at the pulsed source of light energy may be monitored as a guide to varying the light source energy characteristics to best effect contaminant removal.