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The main aim of this work is to measure the activity concentrations of Naturally Occurring radioactive Materials (NORM) produced in the exploration and extraction processes of oil.The natural radionuclides 228U,232Th and 40K,are brought to the surfaces and contain higher radioactivity than surface background..When NORM present in sufficient amounts it may expose people to health hazard.recently NORM subjected to restricted regulation at Qatar state.Twenty two soil samples collected from an inshore oil field at Dukhan area at Qatar,and 10 sludges samples from stored barrel at storage area for some international company.The specific radioactivity of 228U,232Th and 40K,,and its daughter nuclide for all samples were determined using high-resolution γ -ray spectrometry using a hyper-pure germanium detector.226Ra determination throw the γ peak energy 186.1keV with yield 3.28% so its sensitivity is poor beside that this line interfere with 235U γ energy peak energy 185.7keV.Thus 226Ra can be determined more accurate via γ- emitting progeny 214Pb and 214Bi at secular equilibrium,or the specific radioactivity of 226Ra alone calculated by subtracting the specific radioactivity of 235U which is calculated from the peak energy of 143.76 keV from the total specific radioactivity calculated for 226Ra at peak energy186.1keV.Activity concentrations of 226Ra in soil samples collected from Dukhan oil field at the state of Qatar can be regarded as having normal levels of natural background radiation except two samples where the levels(220 and 330 Bq/kg) are higher than the exempted value(185Bq/kg) set by Qatar regular authority.This implying that the increased 226Ra concentration for the 2 samples due to NORM.For sludges samples stored at Mersek store the activity concentrations of 226Ra range from 165.0 - 1253.9 and for Occidental store range between (27885-13984Bq/kg).The radium equivalent activity (Raeq),external hazard index Hex,The absorbed dose rate calculated from activity concentration of 226Ra,232Th and 40K,and The corresponding outdoor and indoor annual effective doses in soil and sludges samples were calculated.Results obtained are discussed and compared with the international recommended data.From this study,it was noticed that the concentrations of NORM in the sludges samples were exceeds the Qatar exempted value.