Evaluation of Laser De Painting System

De-painting aircraft is a standard step in the corrosion control processes found on nearly every Air Force installation. Depot-level depainting processes often use hazardous chemicals to remove coatings from aircraft and support equipment. However, these chemical strippers and sanding techniques typically have serious health and environmental concerns associated with their use as well. These concerns have led to research in alternative de-painting methods. Currently, laser ablation de-painting is being investigated as an alternative andor supplemental de-painting method at the depot and field levels. AFIOH provided an assessment of this process, which took place in a laboratory setting however, all removed coatings were standard aircraft primers and paints from the Air Force supply system. Laser ablation is achieved by using pulsed high energy Class 4 lasers that create bursts of high intensity energy. Laser ablation is a mechanical process. A shock wave is created by vaporizing a thin layer of coating into plasma. The shock wave removes the coating and creates a crack network in the remaining coating. Paint substrates are reduced to atomic levels with some recombination at the molecular level. Portable HEPA ventilation is tied to the system and collects particles and gases at the laser head. AFIOH assessed controls and contaminants created by the ablation including laser hazards, noise, carbon dioxide, carbon monoxide, nitric oxide, hydrogen cyanide, formaldehyde, and metals including chromium VI. Further assessment is still needed, but initial sampling found promising OEL results.