The residuals of a fuel after an explosion in Unit 4 of Chornobyl nuclear power plant (ChNPP) are in uncon-trollable state. This means that the object is potentially dangerous. To control for the lava-like fuel-containing materials and warning about initiation of self-sustained reaction the systems exist, which control neutron flux from fuel-containing materials in destroyed Unit 4 of ChNPP. It is suggested, that rising of neutron flux and exceeding by it some level argues about development of dangerous situation and requires taking some measures. The questions concerning establishing of such a level on the base of existing measurements of neutron fluxes are the subject of this article.
The statistics of neutron flux density over a period of a few days has been analyzed. It was shown, that this statistics do not comes to Gauss or Poisson functions. It was discovered, that values of neutron flux density do not form a continuous series of values, and this can not be explained by the work of electronics. It was suggested to establish two types of control levels of neutrons flux density: the first - for fixing of instant excess of maximal values, and the second - for tracking of slow changing of a mean value.
Keywords: "Ukryttya" object, control level, neutrons statistics, fuel-containing materials.
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