The model generates conservative predictions in which the main contributor to the dose rate of target tissues of the respiratory system is from 伪 radiation arising from 222Rn daughters. Tabulated 222Rn DPURn values are given for 69 species used by the England & Wales Environment Agency for habitats assessments. The approach is then applied to assess the authorised discharges of 222Rn from sites in England, demonstrating that, from a whole-body dose perspective, the biota considered are protected from effects at the population level.