Threats of strike action could see retired firefighters return to the service to provide emergency cover.
Tyne and Wear Fire and Rescue Service confirmed it has contacted ex-workers who had over the last five years.
Union bosses claim letters sent to former firefighters had caused “anger and annoyance”.
Potential recruits who passed the medical, physical and written tests during the most recent recruitment process have also been contacted. These have no official training.
It comes as brigades across the North East prepare for a potential walk-out following a dispute over pension reforms which, the Fire Brigades Union claims, will see its members make larger contributions with no gain.
Assistant Chief Fire Officer Joy Brindle said the service could no longer rely on the military and, unless a deal is struck, it means there could be a walk out as soon as September.
Now the service is offering employees who retired in the last five years positions as “assessment officers” and “emergency fire crews”.
Mrs Brindle said the service was “not proposing that they will be able to take on the full role of a current firefighter” and said the service had a “positive response” to the letters.
But Jim Herron, who stood on the picket line in 1977 during a nine-week walk out, said he was “disappointed”.
The 61-year-old dad-of-three spent 16 years with the service and was branch chairman of the FBU at the East End Fire Station in Byker, Newcastle. He retired in 1991.
Mr Herron, who lives in Whitley Bay, North Tyneside, said: “No one wants to go on strike – I certainly didn’t in 1977 – and it’s obvious they haven’t got the troops to cover it.”
“It’s simply dangerous. There will be people who take the ‘30 pieces of silver’ and there will be people who train these retired officers to do their jobs while others go on strike.
“Tyne and Wear is one of the best brigades in the country.
“This decision is disappointing to say the least. The vast majority of retired firefighters will say no.”
Letters distributed to retired officers stated: “Tyne and Wear Fire and Rescue Service are committed to ‘creating the safest community’ and due to potential industrial action regarding the changes to pensions proposed by the Government it is necessary for the service to recruit the roles [of incident assessment officer/emergency fire crew vacancies – casual hours contract].”
As part of these roles recruits will be required to assess “resources required to attend emergency incidents” with some driving to reported fires “to determine emergency resource requirements”.
Dave Turner, chair of the FBU in the North East, said: “We understand the chief fire officer has a statutory obligation to provide fire cover and we had prior notice that he intended to write to former employees and that is a matter between the Fire Authority and those individuals.
“However, I have had direct contact from a number of former firefighters and all are extremely annoyed.”