I think the reason is as mentioned below:
Citing safety reasons, railways has decided to remove curtains put on pathways of all air- conditioned three-tier (3 AC) coaches of trains. However, the curtains from windows of 3 AC coaches will continue, officials said.
Decision to remove curtains was takenon recommendation of Commissioner of Railways Safety (CoRS) following its enquiry into causes of last year's fire in Bangalore-Nanded Express train, that left at least 26 people in Andhra Pradesh.
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Board had on March 12 decided to remove all curtains put on pathways of 3 AC coaches. All zonal railways have been instructed to remove them," a senior Railway Ministry official said.
The zonal railways will remove the curtains as and when a train undergoes general maintenance works, he said.
Though the curtains were made of fire-retardant material, but considering CoRS recommendation, the board has decided to remove them, the official said.
A major fire had ripped through a third AC coach of the Bangalore-Nanded Express train, killing 26 people, including two children, in sleep and injuring 13 others in the wee hours of December 28, last year in Anantpur district of Andhra Pradesh.
In order to further improve fire safety mechanism in rolling stocks, railways has called a two-day international conference from April 24-25 on fire safety technologies here. Participants from Germany, France, Italy, the US and the UK will be attending the conference, he said.
The railways had in 2009 decided to put curtains in aisles of all air conditioned three-tier coaches, in order to give more privacy to passengers.
Earlier railways has taken back some of its decisions-- extra side middle berth in sleeper train coaches and use of 'kulhar' (earthen pots) after it received flak from travellers.
In order to accommodate more passengers, former Railway Minister Lalu Prasad had in 2008 approved "high capacity coaches" with extra side middle berth seats for sleeper class. The facility was later extended for third AC coaches.
The high capacity sleeper coaches had 81 seats as against 72 in then (and now) existing sleeper class coaches. Whereas, modified third AC coaches had 72 seats as against 64 in then (and now) existing 3A class.
The project had to be rolled back in 2009 after passengers complained of inconvenience due to the restricted sitting and sleeping space, the official said.
Similarly, Lalu's pet project of introducing 'Kulhars' by removing plastic cups also did not get many takers.
Lalu had in July 2004 introduced 'kulhars' which slowly vanished from trains and platforms. However, there is no ban on selling beverages like tea and coffee in 'Kulhars', the railway ministry official explained.