It is recommended in Criterion 19 that PPC with 30% fly ash content should be used. However CPWD mandates the use of IS1489 code. As per IS1489, part 1, section 5 (https://law.resource.org/pub/in/bis/S03/is.1489.1.1991.pdf) fly ash content cannot exceed 25%.
Thus it would be difficult for us to have CPWD agree to 30% fly ash specification when PPC is used. (Please note even in sites using RMC, PPC is kept on site as a backup).
Kindly guide on the way forward.
The link being referred to by you, is of an older version of IS1489. This IS code has been updated in 2015. The newer version has increased the maximum limit of fly ash to 35%. Request you to refer to IS 1489:2015 for the same.