Development of certified matrix reference materials for quality assurance of screening ¹³⁴Cs and ¹³⁷Cs in food

A certified reference material using activated alumina powder certified for activity of (134)Cs and (137)Cs was developed. The results of the verification and the certification are described. The certified reference material can be used for quality assurance of screening activity measurements of (134)Cs and (137)Cs in food/foodstuffs. Commercially available equipments were experimentally tested using the CRM and another CRM including (40)K. The results of these tests are also shown.