Air contaminants which emerge during laser ablation often cause health risks if released in the workplace and decrease laser cleaning efficiency if redeposited at the material surface. In addition, ultra-fine particles are generated if short pulses are applied. Consequently, a description of the nano-particle aerosol generation and the influence of laser parameters and material surface on the nano-particle size distribution are given in this paper. The high respirability of such particles can pose health risks, so suitable capture systems near the processing zone or personal protective equipment such as respiratory masks are required.