This European Standard specifies the characteristics and performance requirements of calcium silicate masonry units mainly intended for use as inner walls, outer walls, cellars, foundations and external chimney masonry. The standard applies to all calcium silicate masonry units, including those of an overall nonrectangular parallelepiped shape, specially shaped and accessory units. It specifies the product characteristics related to, for instance, strength, density and dimensional accuracy, amongst others, measured according to the corresponding test methods contained in separate European Standards. It specifies the evaluation of conformity of the product to this European Standard. The marking requirement for products covered by this document is also specified. This European Standard does not contain standard sizes for calcium silicate masonry units, nor standard work dimensions and angles of specially shaped and accessory units. It does not apply to units with more than 60 % volume of voids, nor products made from shale as a major raw material. It does not apply to storey height panels. It does not apply to calcium silicate masonry units intended for use as a damp proof course, to units with an incorporated thermal insulation material bonded to the faces of the unit susceptible to be exposed to fire, or to chimney flue units. The Committee responsible for this standard is NA 005-06-02 AA "Koordinierungsausschuss Mauersteine (SpA zu CEN/TC 125/WG 1)" ("Coordinating committee Masonry Units (Mirror Committee of CEN/TC 125/WG 1)") at DIN.