ACT Emergency Services Agency commissioner Dominic Lane said the Fairbairn-based communications centre will increase its capability in the first half of 2019 as part of a larger overhaul of the facility.

The changes come following a growing number of triple zero calls in recent years, with more than 64,000 made in the most recent financial year, compared to 63,000 the year before.

While the number of firefighting call outs has decreased, down from almost 12,000 in 2009-10 to 10,500 last financial year, ambulance call outs have surged, rising from 35,000 in 2009-10 to 54,000 in 2017-18.

Mr Lane said the number of additional staff is yet to be finalised.

"We're still in consultation, and it all depends on demand," Mr Lane said.

"We can't say how many, because over the year we expect to grow."

Currently,  there are four officers on hand at all times for fire and rescue calls, three being communications operators and the fourth being in a station officer or manager role.

Existing levels of staff for ambulance call takers is staggered throughout the day, with four staff on between 7am and 1.30pm, five between 1.30pm and 3.30pm, four between 3.30pm and 7pm, three between 7 and 10pm and two rostered on for 10pm to 7am.

ACT Emergency Services Agency director of risk and planning David Foot said ambulance staff numbers would be based around demand during peak times.

"When the higher number of episodes are, that's when we would have our highest ratio of staff in the room," Mr Foot said.

"Morbidities in the elderly and a growing and ageing population are part of a whole range of factors that continues to drive demand for ambulance call outs."

The increase in staff comes as the call centre is set to undergo a major overhaul, with trained firefighters working in the centre to be replaced by civilians, freeing the firefighters to work in the field.

The agency is 18 months into a five-year plan to reform the triple zero centre, with most of the key changes likely to come into effect some time next year.

"At the moment, we're doing consultations," Mr Foot said.

"The clear message is that when a member of the public rings triple zero, they will get the same quality of service. There will be no downturn in the level of service they receive, and resourcing in the room is scaled to meet demand."

Mr Lane said the additional firefighters will lead to significant improvement in response time.

The commissioner said a transitional model will be used at the communication centre before the staff increase and civilian firefighter changes come into effect.

"We will have new call takers and dispatchers working alongside firefighters and then eventually we will increase the number of them and gradually release firefighters back to operational duties," Mr Lane said.

"What we're seeing is a gradual phasing out of firefighters for the role that will be replaced by the call centre dispatcher model."

The move has previously been opposed by the ACT's firefighting union, saying when it was first announced it had no confidence in the plan.

United Firefighters Union ACT branch secretary Greg McConville said there were several concerns.

"We're not opposed to change, but the overriding concern is firefighting and and community safety," Mr McConville said.

"We're not going to accept an open-ended change where there is no detail to guarantee that safety."

Mr McConville said firefighters on hand in the communication centre have skills and knowledge in deploying equipment for emergencies that civilians wouldn't necessarily have.

"It's not as simple as saying just take the firefighters out of the communication centre and the community will be better off," he said.

"It's a question of efficient deployment."

While the measure has been enacted in other states like Victoria and Queensland, the measure has been accompanied by a mobile communication centre that's able to be accessed by emergency crews on the ground.

The union head said no such plan has been proposed for the ACT.

Negotiations between the union and the Emergency Services Agency are ongoing, although Mr Foot said he was confident of reaching an agreement soon.

"Our first priority is the call-taking capacity to support fire operations and delineating into the future," he said.

"The union have indicated concerns with the programs but remained committed [to working with us], and we'll remain confident."

The agency has said more paid positions would be available for people looking to work in emergency management, with training provided.

"All up, the training is about 18 weeks from start to finish, and once they finish, they receive a national qualification for emergency call taking," Mr Foot said.

"Under the process, anyone under those duties would hold that qualification."