The strongest El Nino weather pattern since 1997, which is expected to bring hotter, drier days and more powerful winds in November and December, means it is unlikely last year's mild fire season will be repeated.

"[Because of the mild summer], we were carrying out hazard reduction burns in February [2015]," Mr Stark said. "That is quite unique."

The chief officer, who was hosting the Rural Fire Service's well-attended annual open day on Sunday, said Canberra's status as "the bush capital" meant urban areas could quickly be on the frontline of a fire emergency.

"With our unique planning, with areas like Black Mountain and Red Hill, we have 40,000 dwellings in the ACT that are in bushfire-prone areas," he said. "They are within 100 metres or so of significant bushland."

Although hazard reduction burning programs over the last two years have been successful, there is a lot of fuel on the ground waiting for the right conditions to feed a firestorm.

"This year has been one of the most productive years [for burning] in recent times," Mr Stark said. "[However], 2013-2014 was even better. While that means we are well set up [for the coming season], it doesn't eliminate the risk.

"We couldn't and shouldn't hazard reduce the entire bushland area of the ACT. That would destroy what we are trying to save."

The harsh 2003 ACT fires were among the reasons why Canberra had not experienced such devastating fires in recent years.

However, that is changing.

"That year, 85 per cent of the bush areas of the ACT burnt," Mr Stark said. "But after 10 years, fuel [on the ground] accumulates back to peak levels. We certainly do have, across the ACT, high fuel loads in all our bushland areas [again]."

The ACT RFS emerged from 2003 determined to learn from its worst experience. The fruits of those bitter lessons have been put in place.

"Today [the open day, which was attended by more than 2000 people] is an example of that," Mr Stark said. "Instead of the traditional leaflet in the mailbox, we are having true engagement with the community.

"The whole purpose is to create an environment where people, including families with young children, can come because of the attractions [such as a petting zoo, jumping castles and food stalls] and we can engage them in conversation and provide them with specific information to help them prepare.

"This [RFS helicopter base] facility did not exist in 2003. It was built in 2010. In 2003, the helicopters came from outside Canberra and they landed in a paddock."

The ACT has two helicopters and access to a third from NSW.

The machines are used for fire spotting, water bombing and winching in remote area fire teams who battle blazes in country that can't be reached any other way.

Mr Stark said climate change was having an impact on the frequency of fires, the intensity and the way they had to be fought.

"Without making judgments on what is causing it, we [firefighters] are seeing climate change occurring," he said. "It is going to provide more and more challenges to firefighters and the community [in the years ahead]."