Gurugram, Feb. 12 -- Changes in India's seismic design standards notified by the Bureau of Indian Standards (BIS) in November last year have prompted Gurugram Metro Rail Limited (GMRL) to revise the structural design of the entire Gurugram metro alignment, with stronger safety measures being incorporated into piles, pillars and stations, officials said. Metro officials said designs for piles, pillars and stations are being updated to meet specifications under the new seismic zone notification issued by BIS. Additional designers and planners have been deployed to rework structural designs, though officials said efforts are being made to ensure the revisions do not affect construction timelines. As per GMRL officials, the cost of revision in design is being estimated but it won't have any significant increase in the project cost. The metro corporation said that they are taking steps to ensure the timelines are not impacted. According to the revised seismic design standard IS 1893 (Part 1):2025 and Part 5:2025 issued on November 3, 2025, most new projects are expected to be designed to zone five safety levels, even though the region remains officially in zone four. Experts said the norms require stronger reinforcement and ductile detailing, thicker structural walls, stiffer frames and deeper, more resilient foundations. The updated code replaces the 2016 version and is mandatory for all new construction nationwide, including Delhi NCR.A senior GMRL official said the structural design of pillars, piles, spans and other components is being updated to meet zone five specifications. "Our job has become difficult and more time taking as all structures are being redesigned. The design will ensure that the structures will tolerate stronger earthquakes," the official said....