Section 2(77) in Assam Notified Urban Areas (Other than Guwahati) Building Rules, 2014
(77)"masonry unit" means an unit whose net cross-sectional area in every plane parallel to the bearing surface is 75% or more of its gross cross-sectional area measured in the same plane. It may be either of clay, brick, stone, concrete, sand lime brick or any other construction material;
