${\displaystyle a_{\text{B}\text{,v}}=\frac{{\displaystyle \int {\Phi }_{\text{e}\text{,}\lambda }(\lambda )}\cdot B(\lambda )\cdot \text{d}\lambda }{{\displaystyle \int {\Phi }_{\text{e}\text{,}\lambda }(\lambda )}\cdot V(\lambda )\cdot \text{d}\lambda }}$

where λ is wavelength, Φ_e,λ(λ) is spectral radiant flux, B(λ) is the blue light hazard spectral weighting function, and V(λ) is the CIE spectral luminous efficiency function for photopic vision

Note 1 to entry: Luminous radiation refers to optical radiation weighted with the CIE spectral luminous efficiency function for photopic vision, V(λ).

Note 2 to entry: The use of this term is only reasonable if parts of the optical radiation are in the visible range and thus ${\displaystyle \int {\Phi }_{\text{e}\text{,}\lambda }(\lambda )}\cdot V(\lambda )\cdot \text{d}\lambda \ne 0$.

Note 3 to entry: The blue light hazard factor of luminous radiation has unit one.