UPDATE: ABOUT 100 corporate and technical staff at the Metropolitan Fire Brigade (MFB) have held work stoppages in Melbourne in their bid for better pay.

The workers, including administrative staff and mechanics who are responsible for the upkeep of firefighting vehicles, held a rally outside the MFB's city headquarters during a four-hour work stoppage today.

United Firefighters Union state secretary Peter Marshall said the workers, among the lowest paid in their fields, were demanding a 4.5 per cent pay rise each year for the next three years.

The state government's wages policy is a 2.5 per cent per annum rise.

Mr Marshall said the pay demand was not unreasonable, and the government had treated the workforce - the backbone of the fire service - disgracefully.

"These are the people who actually make the fire trucks go out the door ... these are the people who actually ensure that the firefighters have got the tools to do the job," he told AAP.

"This government does not respect emergency services' work or its support staff."

Negotiations over a new pay deal have been dragging on for more than 12 months.

As part of the work bans, staff are filtering phone calls with voice mail, refusing to process mail and attend meetings, and using their computers with the CAPS lock on.

The administration staff work in areas including fire prevention, research and education, and support roles for front-line firefighters.

In a statement the MFB said the industrial action had not impacted the service's emergency response.

"MFB has been negotiating a new Enterprise Agreement for its Corporate and Technical staff. These negotiations have been progressing at Fair Work Australia," the statement said.

"MFB firefighters are not involved and there will be no impact on services arising from this issue."