Firefighters say they are sick to death of their calls for action on climate change being ignored by the Morrison government.

Dozens of firies have descended on Parliament House to demand more manpower and an end to fossil fuels.

United Firefighters Union vice-president Mick Tisbury said there were no climate sceptics on the end of a fire hose.

"The prime minister of this country likes to make out that he supports firefighters," he said in Canberra on Thursday.

"Supporting firefighters is not bringing lumps of coal into parliament and denying climate change.

"Let us get on with the job, give us the help we need."

The union wants a major boost to the number of firefighters across the country and much greater consistency on the rules around using equipment.

Mr Tisbury said firefighters in different states and territories couldn't communicate with each other over radio or connect hoses to each other's trucks.

This creates serious problem as firefighters move around the country to help their under-resourced counterparts interstate.

Mr Tisbury said it also ran the risk of leaving firefighters fatigued and demoralised when they return home.

"Quite frankly we're sick to death of our message being ignored," he said.

"If I was a lobbyist I'd get in the front door tomorrow, but I'm not, I'm just a firefighter."

He said Australia didn't have enough resources to fight bushfires this summer, having already battled conditions not normally seen until February.

The union could not say exactly how many more boots on the ground were needed.

But it pointed to previous reports recommending a rise of at least 60 per cent in volunteer and professional ranks.

UFU national president Greg McConville suspects the Morrison government may be hesitating to engage because of its so-called union busting bill before parliament.