Gamma activity in Lahore : Pakistani building materials

Abstract EN

Natural r^ioactivity due to 40K, 226Ra, and 232Th has been measured, using a HPGe (high purity germanium) based ■7-ray spectrometer, in samples 0! unbaked clay bricks, sand, cement, aggregate or crush, marble chips, and glass used for the construction of dwellings in the city of Lahore (Pakistan).

The radium equivalent activities and hazard indices have been determined ؛or these materials.

The maximum value of the radium equivalent activity is 319 ±10 Bq kg ' in ceramics, which is less than the normally accepted limit of 370 Bq kg'1.

The maximum values of hazard indices are also less than unity except for some ceramic samples.

Therefore, the materials used for the construction of dwellings in Lahore do not pose a major 7-ray hazard.

The dose equivalent rate due to ■y-rays at the centre of a standard size room is theoretically determined.

Our calculations show that the 7-dose equivalent rate is smaller by a factor of 2.5 if the buildings are made from concrete rather than from clay bricks