Krzysztof Kozak, Jerzy W. Mietelski, Mirosława Jasinska, Paweł Gaca
The Henryk Niewodniczanski Institute of Nuclear Physics, 152 Radzikowskiego Str., 31-342 Krakow, Poland
The methods of passive and active shielding and the results of background gamma measurements, during the years 1996-2000 are presented. The spectrometer background was recorded in various shielding configurations. The ultra-low level gamma-spectrometer (called in the paper the spectrometer E), equipped with a veto-detector for cosmic muons (active shield) was under tests during 1999-2000.