IS 1489-1 (1991): Specification for Portland pozzolana …
4.1 Pozzolrna quantities not exceeding onepercent. 4.1.1 Fly ash used in the manufacture of 5 MANUFACTURE Portland-pozzolana cement shall conform to requirements IS 3812 : 1981 subject to the specified in 4.1.2 and 4.1.3. Porland-pozzolana cement shall bemanufactured either by intimately mtergrinding Portland. 1.