Rail workers are campaigning in Glasgow today to try to speed up work to stop human waste being dumped on to train tracks in the Highlands.
The Rail, Maritime and Transport Workers Union (RMT) want all carriages, which serve Oban, Fort William and Mallaig, fitted with effluent retention tanks by 2016.
Infrastructure Secretary Keith Brown has told MSPs that 479 of 527 ScotRail carriages operating across the country were already connected and the remaining stock would be upgraded by December 2017.
Transport Scotland has confirmed that it had made it a requirement of the new ScotRail franchise – awarded to Abellio and starting in April – that all rolling stock must be fitted with controlled emission tanks.
RMT representatives claim they have been assured by Network Rail that the risk of infection to staff working trackside was low but the last analysis carried out on the impact of human waste was in 2004.
The union claimed their members were not being offered vaccinations against potential illnesses or disease like hepatitis.
RMT General Secretary Mick Cash said: “Activists will be on the entrances at both Glasgow Central and Queen Street tomorrow morning leafleting the public to raise awareness that this filthy and disgusting practice continues in 2015 with little or no regard for the health, safety and wellbeing of rail workers.
“We are determined to force rail bosses to bring forward the date when this scandal is brought to an end once and for all.”