Test mode of operation network of monitoring subsoil radon in the south of Sakhalin Evgeny Makarov, Pavel Firstov, Dmitry Kostylev, Evgeny Rylov and Ilya Dudchenko E3S Web Conf., 62 (2018) 03007 Published online: 07 November 2018 DOI: 10.1051/e3sconf/20186203007