Summary: This study concerns an estimation of the amounts of the activities originating from polyethylene and quartz containers transferred to container surface due to the recoil effect in the thermal neutron-capture process, thus causing contamination of the sample. The universal range-energy relationship given by LINDHARD and SCHÄRFT has been applied in the calculations. As regards containers with impurities in the p. p. m. region, the amounts of activities transferred owing to this effect were found to be quite negligible. However, when the containers were rinsed with hydrochloric acid, activities were found to be extracted from depths of the order of magnitude 10-3 and 10-4 cm in the polyethylene and the quartz materials respectively which in some cases necessitates corrections.