* Develop concept, preliminary, and detailed designs for ECS and TVS systems for metro rail and tunnel projects.* Perform ventilation and smoke control calculations, including airflow, heat loads, piston effect, and emergency operation scenarios.* Design and size supply, exhaust, smoke extraction systems, fans, dampers, silencers, shafts, louvers, and associated ductwork.* Carry out and review CFD simulations for normal and emergency ventilation using tools such as IDA Tunnel, SES, FDS.* Interpret CFD results to validate system performance and support design optimization and safety compliance.* Prepare and review system layouts, schematics, single-line diagrams, and P&IDs for ECS and TVS systems.* Coordinate with Civil, Architectural, Electrical, Fire, ELV, BIM, and other systemwide contractors to ensure integrated designs.* Ensure designs comply with applicable standards such as NFPA 130, ASHRAE, ISHRAE, NBC, and project specific requirements.* Review vendor drawings, technical submittals, equipment datasheets, and CFD reports. Support design reviews, safety audits, authority submissions, and client presentations.* Assist site teams during construction, testing, commissioning, and as-built documentation stages.* Prepare technical specifications, B.o.Qs, and cost estimates for ECS and TVS systems.