The IES has approved five revised or reaffirmed lighting standards: ANSI/IES RP-27-26 Recommended Practice: Photobiological Safety for Lighting Systems Updates include new definition (angular subtense), removal of propagation of uncertainty for wavelength accuracy, improvements to measurement metrics, updates to the relative spectral weighting function for Assessing Actinic Radiation Hazard, and new equations for retinal blue [...]














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