Comparison of excess radiological risk of building materials and industrial by-products according to I-index (EU-BSS) and revised room model (IAEA SSG-32)

To get a better insight into the radiological features of industrial by-products that can be reused in building materials a review of the reported scientific data can be very useful. The current study is based on the continuously growing database of the By-BM (H2020-MSCA-IF-2015) project (By-products for Building Materials). Currently, the By-BM database contains individual data of about 431 by-products and 1095 building and raw materials. It was found that in case of the building materials the natural radionuclide content varied widely (Ra-226: <DL-27851 Bq/kg; Th-232: <DL-906 Bq/kg, K-40: <DL-17922 Bq/kg), more so than for the by-products (Ra-226: 7-3152 Bq/kg; Th-232: <DL-1350 Bq/kg, K-40: <DL-3001 Bq/kg). The average Ra-226, Th-232 and K-40 contents of the reported by-products were respectively 2.52, 2.35 and 0.39 times higher than the building materials. The gamma exposure of bulk building products was calculated according to IAEA Specific Safety Guide No. SSG-32 and the European Commission Radiation Protection 112 based I-index (EU BSS). It was found that in most cases the I-index without density consideration provides a significant overestimation in excess effective dose.

Exploring the influences on classroom-based contact via shared education in Northern Ireland

Initiatives in intercultural education have frequently involved the promotion of contact between members of different groups as a means of improving intergroup relations. Experience from Northern Ireland suggests, however, that such schemes have often been organised and delivered in such a way that opportunities for sustained, high-quality contact are limited. This paper considers processes of contact in one relatively recent initiative, “shared education”, which involves collaboration between separate schools to deliver classes to Catholic and Protestant pupils in mixed groups. Employing qualitative methods of observation and interviewing to capture participants’ experiences of contact, the research explores the influences on the quality and frequency of cross-group interaction in the shared class. With findings highlighting the subject and pedagogy, teacher’s approach and classroom arrangement as key factors, the study offers suggestions for policy and practice to enhance opportunities for contact and relationship-building in mixed classes.