The characteristics of the external radiation on the surface of the casks for spent nuclear fuel (SNF) storage by dry method are investigated for the case when the spatial distribution of SNF in the basket changes due to the destruction of the fuel rod claddings. The surface areas are determined, where the changes in fluxes of neutrons, produced by ²⁴⁴Cm actinide, and γ-quanta, produced by long-lived isotopes, are maximum in the result of the decrease in the height of the SNF area. Concrete (VSC-24) and metal (SC-21) casks are considered as examples. The procedure of periodic measurement of the dose rate of neutrons or γ-quanta at the specified points of the cask surface is proposed for identifying the fuel rod cladding destruction. Under normal operation, the decrease in the dose rate produced by neutrons as the function of SNF storage duration is determined by the half-life of ²⁴⁴Cm, and for γ-quanta - by the half-lives of long-lived SNF isotopes. Consequently, a stepwise change in the dose rate of neutrons or γ-quanta, detected by the measurements, as compared to the previous one, would indicate the destruction of the fuel rod claddings.

针对燃料棒包壳破坏导致桶内SNF空间分布发生变化的情况，研究了干法贮存乏核燃料(SNF)桶表面外辐射特性。表面积被确定，其中中子通量的变化，由²⁴⁴Cm锕系元素和γ-量子由长寿命同位素产生，在SNF区域高度降低的结果中最大。混凝土 (VSC-24) 和金属 (SC-21) 桶被视为示例。提出了定期测量容器表面指定点的中子或γ-量子剂量率的程序，用于识别燃料棒包壳破坏。在正常操作下，作为 SNF 存储持续时间函数的中子产生的剂量率的降低取决于²⁴⁴ Cm的半衰期，而对于 γ-量子 -取决于长寿命 SNF 同位素的半衰期。因此，与之前的测量相比，测量检测到的中子或 γ 量子剂量率的逐步变化将表明燃料棒包壳的破坏。