"PSC or Portland Slag cement is manufactured by either grinding the Portland clinker with gypsum and granulated slag or blending the ground granulated blast furnace slag (GGBS) with Ordinary Portland cement by means of mechanical blenders. Normal composition of portland cement is 30 % clinker, 5 % gypsum and 70 % blast furnace granulated slag. The quality of slag used in cement manufacturing is governed by IS 12089:1987. PSC has been voted as the most suitable cement for mass construction because of its low heat of hydration. Slow hydration of PSC liberates the C-S-H gel over a longer time period thus reducing the pores / porosity of concrete. The dense concrete is more suitable for structures in the coastal regions as the flow of water inside the concrete is restricted resulting in the increase durability of the structure. PSC (in required proportion) offers an improved resistance to sulphate attack from the sea water because of low water permeability, depleted quantum of Ca(OH)2 and C3A content. The physical and chemical requirements for flyash and slag are governed by Bureau of Indian Standards. The BIS codes for flyash and slag are IS 3812 ( Flyash for use as Pozzolona and admixture) and IS 12089 ( Granulated slag)."