Action spectra and estimation of biologically effective UV radiation

The use of action spectra in calculating biologically effective ultraviolet radiation fluence is reviewed. In predicting biological damage due to ozone depletion, the most reliable action spectra are those derived from experiments utilizing polychromatic irradiation filtered by sharp cut‐off UV filters. A new method is presented for optimum estimation of an action spectrum from data obtained in such experiments. Details of the mathematical procedures are discussed, and examples of their use on data from both plant and animal objects are given.