Metropolitan Fire Brigade administration staff involved in one of 2013's more novel industrial actions - which included working with the caps lock on, parking in managers' car spots, and eating lunch in managers' offices - have won pay rises averaging 21 per cent over the next three years.

The pay deal was signed off by outgoing fire chief Nick Easy and came into effect on Christmas Day.

It will see office staff at the fire brigade paid the same as their Country Fire Authority counterparts for the first time.

Along with the pay rises and back pay from the time their last workplace agreement ran out, staff will also get a $1500 sign-on bonus.

The pay rises far exceed the Napthine government's decree that no public sector workers be granted an increase in excess of 2.5 per cent a year unless productivity measures are delivered.

The United Firefighters Union hailed the deal as a victory. The union is simultaneously fighting with the fire brigade and the state government over a new enterprise agreement for Melbourne's 1900 firefighters. Union secretary Peter Marshall said the wages agreement had come with no productivity trade-offs for staff and had been signed after a long delay.

Acting Emergency Services Minister Robert Clark played down the large pay increases, saying they were ''a good win-win outcome''.

He said the pay rises were ''in line with government wages policy'' because they included productivity gains - mainly from the introduction of performance assessments that would recognise higher standards.

Mr Clark said the union's leadership had to explain to members whether opposing the deal and denying them ''a pay rise for eight months was due to incompetence or due to their putting their political interests ahead of their members' interests''.