We have to select motor for smoke extraction purpose. Could anybody would explain about comparison / differentiation of standards for 3 phase 415 volt induction motor. Standards like IEC, BS, NEMA, IS etc. Which is the most relevant / acceptable standard to refer while selecting motor?

If you are in the US, the most referenced standard is NEMA. In Europe, it is mostly IEC.
I believe Germany uses the DIN. Not sure of others. I don't believe there is much difference although voltages and frequencies vary depending on where you are located.