Terrestrial component of natural radiation originates mainly from the primeval radionuclides ²³⁸U, ²³²Th and ⁴⁰K present in the soil. This radiation accounts for more than 80% of total dose received by man from normal background radiation areas (UNSCEAR 2000). Since the levels of natural radionuclides are orders of magnitude higher in High Background Radiation Areas (HBRA) areas, the doses are also proportionately higher in these areas. For example certain regions of the world such as Gaura Pari in Brazil, Yangjiang in China, Ramsar in Iran and Manavalakurichi and Karunagappilly in India, the natural background radiation levels reported are a few manifolds higher than the rest of the world. Significant levels of radionuclides (²³⁸U and ²³²Th) and pockets with higher radionuclide concentrations in the High Background Radiation Area. (HBRA) of the costal Kerala are reported. In view of this, an extensive study is being taken up for assessment of population dose in the area. External gamma levels were measured in the study area on a grid basis covering the area with respect to monazite deposit in the region. In this study a comparison is made with gamma levels measured by survey meter and gamma doses computed from ²³⁸U, ²³²Th and ⁴⁰K values estimated from the soil samples collected from respective sampling locations. Results show an excellent correlation between gamma levels measured by the survey meter and computed values from radionuclides concentrations.