  In situ, high-resolution, gamma-ray spectrometry of a total number of 70
outdoor and 20 indoor representative measurements were performed in
preselected, common locations of the main urban areas of Cyprus. Specific
activities and gamma absorbed dose rates in air due to the naturally occurring
radionuclides of Th-232 and U-238 series, and K-40 are determined and
discussed. Effective dose rate to the Cyprus population due to terrestrial
gamma radiation is derived directly from this work. The results obtained
outdoors match very well with those derived previously by high-resolution gamma
spectrometry of soil samples, which were collected from the main island bedrock
surface. This implies that the construction and building materials in urban
areas do not affect the external gamma dose rate; thus they are mostly of local
origin. Finally, the indoor/outdoor gamma dose ratio was found to be 1.4 +-
0.5.
