The Government is due to finalise the details on how airport testing will work in the next two weeks.
The Green Party leader says it is a complex issue and that testing everyone who passes through an airport would not work.
"You have to be careful that you don't take from the testing capacity that we need in the State within our public health system. More likely it would apply where you would take a test a period of time before flying, because that is what other countries are doing.
"I think it meets some of the public health concerns, that you are not missing people at the airport."
This comes as Ireland's 'green list' is due to be updated from midnight tonight.
Germany, Poland, Iceland and Lithuania have been removed from the list, leaving just four countries: Finland, Cyprus, Latvia and Liechtenstein.
Passengers arriving into Ireland from the four remaining countries included on the list are not required to isolate for 14-days.
However, passengers leaving Ireland are warned that they are still subject to Covid-19 restrictions in the country they are heading to.
Currently, Finland and Cyprus both require proof of a negative Covid-19 test no older than 72 hours, while Latvia requires passengers arriving from countries with a 14-day incidence rate above 16 to isolate for a 10-day period. This would apply to Irish passengers as Ireland's current rate is 78.1 according to data from the European Centre for Disease Control and Prevention (ECDC).