New Delhi, April 13 -- The Delhi Metro Rail Corporation (DMRC) has begun a mid-life refurbishment of its oldest Blue Line trains to improve passenger safety, comfort and overall travel experience, a statement said on Sunday. Under the initiative, the DMRC is upgrading its earliest rolling stock (RS-1) trains, many of which were inducted between 2002 and 2007 and have completed nearly two decades in service, it said. According to the statement, the upgrades are meant to bring these trains in line with current technological and safety standards. A total of 70 trains operating on the Blue and Red lines are being refurbished in phases. Twelve trains were upgraded in the first phase and 18 in the second. Work on additional trains is set to begin shortly. As many as 22 more Blue Line trains are scheduled to be refurbished by November 2027 in the third phase, the statement said. DMRC managing director Vikas Kumar recently inspected the first train refurbished under the third phase before it was reintroduced into service.pti...