BS 6073-2:2008 pdf free.Precast Concrete Masonry Units - Part2: Guide For Specifying Precast Concrete Masonry Units. This British Standard gives guidance for specifying precast concrete masonry units conforming to BS EN 771-3 and BS EN 771-4. 2 Normative references BS 5628-3: 2005, Code of practice for the use of masonry - Part 3: Materials and components, design and workmanship. BS...