Energy density, power density and linear power density are physical quantities representing the laser-induced damage threshold and are intended to define a confidence level in optical components for the application. As long as the relevant qualification parameters match the application conditions, this works well and is standardized by ISO-21254. If this is not the case, scaling laws and boundary values are documented in comprehensive literature: Mostly known the pulse duration scaling in the short pulse duration regime, the indication of the linear power density for long pulses and large optical components, limitations to the applied laser beam diameter concerning defect distributions, or the repetition frequency scaling of the damage threshold. The diversity of the individual constraints is a result of more than 50 years of intensive and interdisciplinary research in the field of laser-induced damage in optical materials.