An original method of organizing protection from the external background during gamma-spectrometric and radiometric measurements is considered, in which the inner surface of the walls, floor and ceiling of the laboratory room is covered with a solid screen made of natural materials with a low content of radionuclides. The use of this method makes it possible to eliminate the cost of purchasing traditional metal protective chambers used for low-background gamma-ray spectrometry and radiometry, and to remove restrictions on the size of the measured sample set by the internal dimensions of the measuring cavity of the protective chamber. It has been established that natural carbonates with a CaCO3 content of at least 98% are the optimal materials for these purposes. The boundaries of the application of this method of protection organization have been determined, and experimental confirmation of the effectiveness of the proposed method has been carried out by measurements in the Cretaceous cell of the Divnogorsky cave temple. A sketch of the layout of the laboratory room has been developed, which implements the proposed method of protection from the external background during measurements