Testing which is the fitter position sensor for a cyclotron liquid target

•We tested position sensors into cyclotron irradiation room.•The position sensors were subjected to gamma radiation and neutrons.•The inductive proximity sensors did not pass in test.

The [18F]FDG has 109.7 min half-life, there is a period about 6 h between the beginning of [18O]H2O irradiation until the PET–CT exam. Any fail in production chain will result in delay to the PET–CT exam. The absence of the position signs from [18O]H2O target valve may result in 18F production loss. Three types of position sensors were tested. After finding the fitter sensor it was possible to reduce the incidence of fails, increasing the reliability in [18F]FDG production chain.