is electromagnetic radiation—typically in the ultraviolet (UV) and short-wavelength visible light spectrum—that is capable of inducing photochemical reactions or biological changes. Key Characteristics
: Unlike standard irradiance (which measures radiation on a flat surface), actinic flux is measured as the total radiation received at a point from all directions ( actinic radiation
: It possesses sufficient energy to break chemical bonds, leading to effects like the photo-dissociation of molecules. actinic radiation