Construction giant Geocon will be served a "please explain" after topless women served beer to a crowd of men at a work party on Friday afternoon.
Women clad in G-string underwear could be clearly seen from the street opposite the construction site, which is adjacent to a Lutheran church and within walking distance of a school.
The event, which began about 3pm, was held to celebrate the safe and successful construction of Canberra's tallest residential tower, Wayfarer.
Geocon managing director Nick Georgalis, who said he was not at the site on Friday, stressed the event was not representative of the company's culture.
"Whatever comes out of today is not going to be dismissed," he said.
"I need to re-evaluate what is acceptable for this sort of event to celebrate achievements. We want to be open and have a progressive attitude towards men and women."
Fairfax Media is aware of at least one worker who was uncomfortable with the presence of strippers at the work party.
Unions ACT secretary Alex White said he was aware of other workers who were uncomfortable and said the event cast Geocon in a bad light.
"It's a disappointing return of old practices from the bad old days 30 or 40 years ago," he said.
"There are women on that site and this raises the question of whether they are comfortable at work.
"There are also questions about the appropriateness of having entertainers on a construction site. This is a dangerous place and I hope the safety of those women was taken into consideration."
Worksafe ACT commissioner Greg Jones said he would investigate the matter with Geocon management early next week.
"I am aware they closed their site to construction activity on Friday afternoon," he said.
"If the site was closed then there are no immediately apparent work and safety issues, but we will make sure we have a full understanding of what happened and why."