RAM Frame - IS 1893:2016 Response Spectra Analysis Scale Factor

Could someone please confirm that scaling the Response Sectra Analysis generated in RAM Frame using the Indian Standard IS 1893:2016 code does not include an adjustment for the Zone Factor, Z?  If this is the case, I would assume the scale factor should be what some call the direction factor = (Z/2)*(I/R)?

This scale factor was recommended for STAAD.Pro with Response Spectrum (https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/12317/is-1893-part-i-2002-response-spectrum-philosophy)

The current FAQ on this subject only mentions scaling by I/R which would apply to ASCE 7 for example (https://communities.bentley.com/products/ram-staad/w/structural_analysis_and_design__wiki/4029/ram-frame---dynamic-analysis-faq).  

I would also note that if this is the correct starting scale factor, I'm assuming an iterative approach needs to be taken using this factor on the first run, then comparing with the base shear from the equivalent static method (some would interpret this to mean using a dynamic analysis but with Ta fundamental period as used in equivalent static method) and adjusting the scale factor so that at least that base shear is maintained as a minimum (IS 1893:2016 7.7.3).

Thank you,

Dan