All the six coach trains will have the number 6 marked prominently on the front and rear of the trains.
The windows of the train operator's coach (the first and last coaches of the trains) will also have the number 6 marked prominently on them, a DMRC spokesman said.
The move comes after passengers were put to inconvenience without knowing whether the train approaching the station was a four-coach or six-coach one. It is also aimed at ensuring even distribution of passengers in all the coaches.
Apart from these identification marks, prior announcements are being made before the arrival of the six coach trains to the stations.
Additional Customer Facilitation Agents (CFAs) have also been deputed at the busy stations for the assistance of the commuters, the spokesman said.
Delhi Metro introduced six-coach trains in Dec on the Noida Line.
Currently, there are 6 six coach trains operational on Line 3 (Dwarka Sector 21 to NOIDA City Centre/Anand Vihar ISBT) and two six coach trains on Line 2 (Jahangirpuri to HUDA City Centre).
By the end of 2011, there will be a total of 95 six coach trains.
On Line 2, there will be 54 six coach trains and six four coach trains and on Line 3, there will be 39 six coach trains and 32 trains of four coaches each.
By the end of the year, a total of 208 train sets will be operational on the Delhi Metro network of which 113 will be four coach trains.