Construction of a biological ''concrete'' wall The Joint Research Centre's Institute for reference materials and measurements (IRMM) intends to publish an invitation to tender for the construction of a biological 'concrete' wall alongside the Van de Graff building of the IRMM. The call should be published in spring 2001 s... The Joint Research Centre's Institute for reference materials and measurements (IRMM) intends to publish an invitation to tender for the construction of a biological 'concrete' wall alongside the Van de Graff building of the IRMM. The call should be published in spring 2001 so that work can commence in the summer of that year. rk