Anyị bụ ndị na - ebubata ngwa ahịa kachasị mma nke ụlọ ọrụ x-ray, anyị na - enye ọnụ ọgụgụ ndị na - eme ihe nkiri nke ụwa. Na ndepụta ndepụta nke a na-ere ahịa na-agụnye: ụzọ a na-ere ere, windo na-eduga na windo iko, na-eduga na mpempe akwụkwọ nchekwa nchekwa na-akụzi na-akụzi ngwaahịa nchebe radieshon. PB nhata nke mpempe akwụkwọ na-eduga na 1pb, 2pb, 3PB, 4PB, 5PB, kilomita 8PB dị ka ndị ahịa si kwuo.