Tech company Wing says it will continue to refine its contentious household delivery drone service, as testing showed the aircraft exceeded suburban noise limits during flights.
The federal infrastructure department has conducted noise testing on the drones as it continues to monitor the roll out of Wing's service across Gungahlin.
The drones produced a noise level of 69 decibels when measured from a distance of 15 metres, according to the results of a June test published earlier this week on the department's website.
That is equivalent to the sound of a busy office.
The reading exceeds the 45 decibel daytime noise limit enforced across Canberra's residential suburbs.
A spokeswoman for Wing said the 69 decibel reading was the "peak sound", which could be heard during a delivery.
The spokeswoman said the Google-linked company "continually" improved its aircraft and operations in response to feedback from the community.
She said the most significant advancement was the use of a special "noise abatement propeller" on its new-model drones.
The quieter model drone, which was unveiled at the end of Wing's controversial trial in the Tuggeranong suburb of Bonython, was used during the June test.
"Our newest aircraft are now equipped with this propeller design, and we intend to use that technology on our delivery drones going forward," she said.
The department has been investigating possible noise restrictions for commercial and recreational drones since June, after conceding that the technology should be subject to regulation.
The national review was prompted by the ACT Assembly's drone inquiry, during which it emerged that no territory or federal agency had direct oversight over noise regulations.
An infrastructure department spokesman said an issues paper would be released later this month as part of the review, which would examine "the assessment of noise levels".
The spokesman would not be drawn on questions of whether the noise level recorded for Wing's drones was reasonable in a suburban environment.
An ACT government spokesman said it would lodge a submission to the review.
The review was expected to be finalised by the end of the year.
The department has said it won't take retrospective enforcement action against drone operators once noise regulations were set.
Wing has been given approval to operate until January 2020, with flights permitted in Crace, Palmerston, Franklin and Harrison.
However, it is restricted to 40 flights per day in each suburb.
Online retail giant The Iconic last month became the latest outlet to partner with Wing to have its products delivered via drone.
Drummond Golf, Mexican eatery Guzman y Gomez and Pure Gelato are among the retailers already on board.