Regime 3 — Thermal Decontamination

Thermal decontamination uses laser-induced heating to decompose or oxidize organic contamination at the substrate surface without ablating the substrate itself. Rather than exceeding the material's ablation threshold, the process operates below it — laser fluence heats the surface to the decomposition temperature of the organic layer (typically 300–600°C for oils, lubricants, and biological films) while the substrate temperature remains below its damage threshold.

This is the dominant mechanism for cleaning lightly contaminated food-contact surfaces, optical components, and precision metal parts where any material removal is unacceptable. The practical limitation is selectivity: if the substrate and contamination have similar thermal properties, the operating window narrows and real-time temperature monitoring becomes necessary.