Firefighters in the borough are being urged not to sign contracts committing them to anti-terror work as part of an ongoing dispute with county fire bosses.
Trials which had seen crews in Wigan, Leigh, Hindley and Atherton carry out emergency medical responses were stopped in September.
But Fire Brigades Union officials have confirmed there are still extra duties they insist are being recommended to their members which are beyond their remit.
One is an initiative known as MTFA (Marauding Terrorism and Firearms capability), which involves firefighters at Leigh, Heywood and Ashton-under-Lyne.
Branch secretary Gary Keary, in a bulletin to members, said: “Employers consider to be contractual working (even though they have provided no evidence for this, nor have they entered into negotiation to vary our members contracts) for our members at Leigh, Heywood and Ashton.
“The national union is very clear that any MTFA response provided by FBU members is done so an entirely voluntary basis and that MTFA is outside of our role, therefore non-contractual.”
Andy Dark, the FBU’s deputy general secretary, said he had been contacted by firefighters from different services across the country, expressing similar concerns over MTFA being considered as a contractual obligation.
He said: “We remain hopeful that government will cease urging local employers to cajole firefighters, of all ranks, to undertake this work via an individual, and not collectively agreed, contract, and redirect its efforts and resources into providing the required funding for fire and rescue services.”
However, fire chiefs insist the initiative is a vital tool in the fight against terrorism.
Tony Hunter, Greater Manchester Fire and Rescue Service’s assistant county officer, said: “Working alongside police and ambulance colleagues, Greater Manchester has had a Marauding Terrorism and Firearms (MTFA) capability since 2010 following an increased threat of terrorism in the UK.
“Throughout that time MTFA has been part of the role of any operational firefighter who volunteers to work at the particular stations that have this capability in Greater Manchester, one of which is Leigh.
“With this comes dedicated training, specialist equipment and realistic multi-agency training exercises that are carried out throughout the year to maintain skills, test procedures and ensure effective joined up working.”