NF P12-109/A1*NF EN 772-9/A1:2005 Methods of test for masonry units - Part 9 : determination of volume and percentage of voids and net volume of clay and calcium silicate masonry units by sand filling.
2005NF P12-109/A1*NF EN 772-9/A1:2005 Methods of test for masonry units - Part 9 : determination of volume and percentage of voids and net volume of clay and calcium silicate masonry units by sand filling.