Targeted approach for ultraviolet disinfection of surfaces

An embodiment may involve obtaining a three-dimensional image map of m surfaces within an environment, wherein the surfaces are associated with importance weights that represent how frequently the surfaces are expected to be touched; determining a set of n vantage points for a light source within the environment; calculating an m×n irradiance matrix for each of the surfaces when the light source is in each of the vantage points, wherein each entry in the m×n irradiance matrix is determined by: (i) rasterizing the three-dimensional image map, (ii) identifying a set of visible surfaces, and (iii) calculating an amount of light-based power that would reach each of the visible surfaces; determining a set of n dwell times for the vantage points; and providing instructions, to a disinfecting agent, to traverse at least a subset of the vantage points, pausing at and illuminating at least some.