In practice, older specs often had fewer performance based requirements and less emphasis on storage stability under longer logistics chains. Current standards typically tighten sieve residue, stability, and compatibility requirements, and they more frequently include residue performance parameters aligned with modern pavement designs. They also tend to require clearer batch documentation, traceability, and defined test methods. The only safe way to compare is to review the exact dated IOCL document versions because changes are periodic and grade dependent. For procurement, always reference the latest published standard and require COAs showing compliance to that revision.