SPECTRAL EMISSIVITY
Definition
The <SPECTRAL EMISSIVITY> is a <Property> that is a <RATIO> of how much <RADIATION> is emitted by a <SURFACE> at a specified <WAVELENGTH> to the radiation from an <IDEAL BLACK SURFACE>> at the same <TEMPERATURE> as given by the Stefan–Boltzmann law. The ratio varies from 0 to 1. Defined in ISO 80000-7 (2008) 7-21.2