[en] We have investigated material susceptibilities to atmospheric neutrons by calculating nuclear cross sections for every natural element from carbon to bismuth. The alpha emitters that can be present in microelectronic devices have also been identified. To improve the performance of microelectronic devices, the semiconductor industry has introduced a number of chemical elements in the device process. These elements experience a natural flux of neutrons and can also contain natural radioactive isotopes. In both cases, device reliability can be compromised. We show that, at ground level, the introduction of an element may be more important than the effect of neutrons