Laser-induced injury of the skin: validation of a computer model to predict thresholds

The exposure and emission limits of ICNIRP, IEC 60825-1 and ANSI Z136.1 to protect the skin are based on a limited number of in-vivo studies. To broaden the database, a computer model was developed to predict injury thresholds in the wavelength range from 400 nm to 20 µm and was validated by comparison with all applicable experimental threshold data (ED₅₀) in the wavelength range from 488 nm to 10.6 µm and exposure durations between 8 µs and 630 s. The model predictions compare favorably with the in-vivo data with an average ratio of computer prediction to ED₅₀ of 1.01 (standard deviation ± 46%) and a maximum deviation of 2.6. This computer model can be used to improve exposure limits or for a quantitative risk analysis of a given exposure of the skin.