The instruction was met with derision by rail unions, who said members would refuse to take scissors to their clothes or turn hats back to front.
Dutch firm Abellio, which takes over the train operator next Wednesday, has asked staff to remove all traces of outgoing FirstGroup from their uniforms.
It has started designing new uniforms but they are not due to be introduced until the autumn.
By contrast, ScotRail staff received new uniforms at the start of First’s franchise in 2004.
Incoming Caledonian Sleeper operator Serco said its staff would also have new uniforms when it takes over next Tuesday.
Abellio has issued a “how to” guide to show employees how to alter their clothing.
The memo stated: “As of 1 April, we need to make sure that all of your uniform items no longer show the First logo, so we have put together a guide to show you the steps we’d like you to take.
“This can be done at home ready for day one or, if you’d prefer to do it at your station/depot on the day, we’ll make sure you have the materials on hand to do so.”
Alterations required include First-branded tags being “carefully cut” from trousers, skirts, shirts, gloves and scarves.
Staff will be given new ScotRail badges to be worn over pink First logos on jackets, waistcoats, fleeces, polo shirts, jumpers and anoraks. They will have to “carefully cut away” stitched First logos on outer jackets, and wear the new badges on top.
Jackets with logos on the collar will have to be kept turned over. New tabards will also have to be worn over other jackets to hide the First logo, and branded zips removed. Rims on woolly hats with the First logo will have to be turned over.
Train drivers union Aslef said members would be ignoring the instructions. Scottish secretary Kevin Lindsay said: “Staff have told me they are embarrassed by this idiots’ guide and feel Abellio and ScotRail management are taking them for fools.
“Aslef members will continue to wear the agreed uniform that is provided, including union ties. Once we agree a new uniform, our members will wear that, but they certainly won’t be taking scissors to the existing uniform and turning hats inside out.”
The Rail Maritime and Transport union described the guide as “nonsense”. Scotland regional organiser Mick Hogg said: “It is absolutely disgraceful. We are talking about peanuts to have proper uniforms in place. This is ridiculous.”
An Abellio spokesman said: “Firstly, it is important to note that de-branding the FirstGroup uniforms for day one of the new franchise is a contractual legal requirement and is also important to avoid confusion for customers and the public.
“Whilst some comments have been made by the trade unions, we believe a large majority of ScotRail people do not see this as a major issue.
“Indeed, many have already been doing it voluntarily in advance of the guidelines sent out.
“De-branding uniforms is standard practice on a franchise handover, and we’re grateful for the cooperation we’re receiving.
“New uniforms have not been issued for day one because we are engaged in a thorough consultation with staff across the network to ensure that the final designs are attractive, practical, and suitable for all working conditions.”
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