Jon has over 10 years' experience in radiation protection including performing radiological assessments and developing the underlying models and tools. He is part of the development team of the Level-3 (off-site consequences) Probabilistic Safety Analysis Code PACE, for evaluating the consequences of radiation accidents. He also has experience in modelling the transfer of radionuclides through the terrestrial foodchain, for example, with UKHSA's tool FARMLAND. He was involved in UKHSA contributions to WHO and UNSCEAR assessments of the levels of exposure to members of the public following the Fukushima-Daiichi nuclear power plant accident in 2011.