On the date of survey, the earthquake-stricken area of Bam was divided to 13 zones. The samples were proportionally distributed in 8 zones, based on a rough estimate of the total number of tents.

To determine the clusters, with the help of an available map and a native who was well familiar with the city, each zone was divided to some sections by half of required clusters. In each section, the main squares and cross-roads were determined and one of them was selected randomly.