A new approach to air travel across Europe has come into operation.
As part of the European Union's traffic light system, countries and regions within those countries, will be categorised as green, orange or red depending on Covid-19 risk levels.
The European Centre for Disease Prevention and Control will publish a weekly map determined by the 14-day incidence and positivity rates of the disease.
People arriving in Ireland from red regions are required to restrict their movements for two weeks.
Passengers from orange regions can avoid the restriction, if they have a negative coronavirus test result taken no earlier than three days prior to departure.
Travellers from green regions can enter the State without restricting their movements or undergoing a test.
Currently, only Greenland is in the green category, with Norway, Finland and parts of Greece in orange, while all others areas are red.
Anyone arriving from Denmark must restrict their movements for two weeks regardless of the traffic light rating over concerns about the new strain of Covid in mink there that has spread to humans.
Under the new system, passengers travelling on certain essential functions do not have to restrict their movements.
This includes essential workers, journeys for imperative business or family reasons (for example, attending a funeral) and essential medical reasons for travel.
The Government has also said a mechanism is due to be in place by December whereby people coming from red regions can be tested here after five days.
With Ireland at Level 5, the current advice remains that there should be no non-essential international travel.
New system welcomed for safe travel
Aer Lingus said in a statement that it welcomes the introduction of a testing regime to facilitate the European traffic light system.
It said: "It represents a positive initial step towards facilitating increased safe international travel, which is critical to the Irish economy."
Aer Lingus said it believes that over time, it should result in a "meaningful increase" in safe international travel and lead to a limited form of random rapid testing for passengers arriving from orange countries or regions, and pre-departure testing for locations classified as red.
There have been 21 million fewer passengers through Dublin Airport so far this year compared to last year.
The daa says Covid-19 has had a devastating impact with only 7 million passengers travelling through the terminals between January and October this year.
It says this is 76% decline on the same period last year.
Some passengers arriving or departing from Dublin airport have been paying for private tests.
Vida Care says it's drive-thru testing facility at the Carlton Hotel at Dublin Airport has been inundated with bookings for its €190 private test.
Conor Kelly, Vida Care CEO, said: "we are already heavily booked for December. We are besieged with calls from Irish people living abroad who want the peace of mind that a private test brings so they can get on with reuniting their families".
However even with a negative test result within 24 hours they must adhere to Government guidelines and restrict their movements.
The Carlton also launched a "Test, Rest and Fly" package today.
Two new drive-thru Covid-19 testing centres will be fully operational at Cork and Shannon Airports from Thursday.
Irish Healthcare company RocDoc says results will be available within a few hours.
David Rock, Chief Executive of RocDoc said "while our focus will be to provide testing for passengers flying in and out of airports, our facility will also be open to members of the public who wish to have a test or local businesses".
Additional reporting Dyane Connor