Health officials have ramped up testing of Canberrans returning to the ACT from South Australia, screening passengers for COVID-19 symptoms upon arrival at the airport.
It comes as South Australia recorded 18 cases of COVID-19 in the past 48 hours following a new outbreak of cases in the state, leading to restrictions being reimposed.
Passengers returning from South Australia will be screened for COVID-19 symptoms upon arrival from Adelaide.
Those with symptoms will be asked to isolate until a test result is available.
Testing began for those on a flight arriving into Canberra at 6pm on Monday, along with another flight 15 minutes later.
Two further flights from South Australia were expected to arrive in Canberra on Tuesday. ACT Health said the approach was similar to that from earlier in the year when Victoria was the epicentre of new cases of COVID-19 in Australia.
A similar approach is also being carried out for passengers arriving into NSW from South Australia.
The border between SA and ACT will remain open, although the ACT Health Minister said the situation could change if case numbers escalate.
ACT Health Minister Rachel Stephen-Smith said while border will remain between the two jurisdictions, the situation could change if case numbers further escalate in South Australia.
"We will continue to monitor cases in South Australia and take appropriate steps to protect the health and safety of Canberrans," Ms Stephen-Smith said.
"Movement between the ACT and South Australia remains open and there is no requirement for returning travellers to quarantine, unless showing symptoms.
"There are no current plans to change this arrangement."
Canberrans will only need to isolate if they show any symptoms after returning from a hot-spot area.
The new outbreak in South Australia is believed to have been linked to a quarantine hotel in the state.
While many states closed borders with South Australia - including Western Australia, Queensland Tasmania and the Northern Territory - the ACT and NSW is still allowing travel between the two jurisdictions.
The closing of borders has cast doubt on all states opening up all their borders by Christmas as previously planned.
Those from South Australia looking to enter states such as Western Australia can only do so after 14 days in quarantine.
Ms Stephen-Smith said Canberrans who had returned from South Australia should remain vigilant after they return home.
"ACT Health is advising anyone who has been in South Australia to closely monitor symptoms," she said.
"If you have been to an identified area of exposure, you must immediately get tested and self-isolate until you receive your result."
The ACT recorded zero new cases of coronavirus in the 24 hours to Monday.
The ACT Health Minister said the recent outbreak of new cases in South Australia was a reminder that COVID-19 cases were still in the community.
"We know that the pandemic is not over, and this is another example of how quickly the situation can change and why we all have to remain vigilant," Ms Stephen-Smith said.
"As restrictions across the country begin to ease, we will continue to see outbreaks of COVID-19.
"Responding appropriately to these outbreaks is important as we learn to live with the virus."
South Australia has imposed a raft of new restrictions to help deal with the new outbreak, including a ban on community sport with gyms and recreation centres in the state to close.
Funerals will be capped at 50 people while licensed venues will also have a cap of 50 patrons.
Workers are being urged to work at home and to avoid unnecessary travel.