Natural radioactivity and associated radiation hazards in local portland and pozzolanic cements used in Jordan

الملخص EN

Activity concentration of the natural gamma-emitting radionuclides (40K, 226Ra and 232Th) in at least forty samples of local Portland and Pozzolanic cement types is measured.

The measurements were performed using gamma spectrometric techniques.

The range of the mean specific activity (minimum and maximum values) due to all the three radionuclides is found.

Radiological hazards of the different samples are estimated using five approaches; the representative level index, the external hazard index, the internal hazard index, the radium equivalent index and the absorbed dose rate.

Some of the measured radiological hazard parameters are compared to similar parameters in different countries.

The activity concentration of 226Ra for all types of cements varies from 29.1±2.01 to 79.2±3.90 Bq.kg−1.

The activity concentration of 232Th for all types of cements varies from 5.8±1.1 to 26.4±1.9 Bq.kg−1.

The activity concentration of 40K for all types of cements varies from 231.9±9.8 to 298.0±10.7 Bq.kg−1.

The radium equivalent activity concentration, Raeq, of the total activity of each cement type is obtained.

The highest value of Raeq was seen in white cement (125.49 Bq.kg−1) and the lowest in Portland Pozzolanic cement (5%) with an average value of (78.08 Bq.kg−1).

Based on the assessment of potential radiological hazards as inferred from the calculations of Raeq, representative level index and the dose rate, the investigated cement samples fall within the category of accepted building materials and are safe to use for the construction of inhabited buildings.