TRAIN operator Metro is quietly removing pay phones from its stations, secret documents reveal.

Drafts of Metro's revised Customer Service Charter, obtained by the Greens using Freedom of Information laws, reveal the plan, which has angered a commuters group.

Greens leader Greg Barber said the charter available online promised "public telephones in operating order at all stations".

"In 2010 the CEO of Metro, Andrew Lezala, sent the Government a revised draft that deletes 'at all stations'. In later drafts, the two sections that mention public telephones are removed completely," Mr Barber said.

Sources told the Herald Sun it was becoming more difficult to find a hard copy of the charter at stations.

Mr Barber said public phones were a safety measure at stations.

"Not everyone has a mobile phone, and it's the more vulnerable groups like children and older people who are less likely to have a mobile paid up and charged up when they get off their train at night," he said.

"People use public phones to call someone to pick them up from the station, or a taxi, and it is back-up if the emergency button isn't working."

Metro spokeswoman Larisa Tait said personal mobile phone use had increased over the years while the use of public phones had decreased.

"Taking this into consideration, it was decided that repairs to damaged or faulty public boxes was becoming too costly as they were rarely being used," she said.

"If any of our customers find themselves in an emergency or need to make an urgent phone call, we would encourage them to inform our staff members who have access to both a station phone and a mobile phone.

"In the event of an emergency, customers can also press the red button on station platforms and in every train carriage."

Public Transport Users Association president Tony Morton said Metro might have been able to get away with not providing public phones if every station was staffed full time.

"We are angry that we now have a situation that in an emergency someone on a station could be without any means to contact emergency services," he said.

"The red button really isn't good enough. VicRoads provides emergency phones on all of our highways in Victoria. I am sure if VicRoads were to rip them out and replace them with little red buttons there would be an outrage."

Ms Tait said some premium stations might have run out of the 2012 version of the charter and were waiting for the updated 2013 version.

amelia.harris@news.com.au