The brigade has shared fire control, risk management and IT functions with Hereford and Worcester Fire and Rescue Service since autumn last year.
Chief Fire Officer Rod Hammerton told the Shropshire and Wrekin Fire and Rescue Authority, which voted to adopt the 16-page agreement, that a fourth branch, procurement, had been added.
But he stressed this did not mean the two brigades would buy everything jointly. Some items, such as stationery, can be more efficiently purchased in partnership with local authorities, while others, like uniforms, were better ordered in collaboration, Mr Hammerton said.
“This agreement, that our legal team have drawn up with Hereford and Worcester’s, frames the overall alliance and describes the actual operations of it,” he said.
“The way I have explained it in public is that is a formal recognition of the deepening and broadening relationship that has existed so far.”
He called the agreement a significant milestone that “maximises opportunities to work in certain areas”.
The agreement continues the current arrangement, where the fire alliance strategic board comprises the chairmen and vice-chairmen of both fire authorities and the chief officer of both brigades.
Authority chairman Eric Carter said: “Certainly, it’s not a takeover on either side. It’s an alliance, and I believe it will very much be a benefit to our communities.”
Two of the agreement’s 17 sections are titled Termination and Consequences of Termination, and another governs Dispute Resolution.
Officer Hammerton said: “This agreement will also serve as a bit of a ‘pre-nup’. If we get into a situation where we want to go our separate ways, we will have a framework for that.”
Hereford and Worcester Fire Authority will discuss adopting the agreement when it meets on October 15.
Shropshire and Wrekin Fire and Rescue Authority also voted to wind up its arms-length training and consulting company, Shropshire Fire Risk Management Services Ltd.
Deputy Chief Fire Officer Andy Johnson told the authority the company was set up in 2013, and worked with more than 300 businesses in the county before being put into hibernation in 2017.
A report, co-authored by Mr Hammerton and Mr Johnson, said the company would not be financially sustainable without significant investment, and recommended it be closed down and its debts to the authority – its only creditor and sole shareholder – be written off.
Officer Johnson said: “It’s classed as a debt, but really it’s paying the wages of the area manager who was employed by the service. It’s a debt only in technical terms.”