The ACT's safety watchdog says it has been checking safety plans for Canberra's construction sites, in the wake of the weekend bridge collapse.

Work Safe ACT's Mark McCabe says some companies have suspended work while they make sure everything is in order.

The Construction Union is also visiting sites along the Gungahlin Drive extension to check for problems.

The CFMEU's Jason O'Mara says so far only minor breaches have been identified.

"There are still some existing issues regarding emergency procedures on the job," he said.

"Some of the companies fail to keep proper site registers and in the case of an event like an incident like we had on Saturday I would have some doubts about them keeping track of everyone on the job."

Nine construction workers were taken to hospital with injuries after the weekend collapse and one man was trapped for 15 minutes.

The highway had been closed at the time while concrete was poured on a new span of the bridge.

A man has spoken about his son's fall during the bridge collapse.

Colin says his son was working on the top of the bridge and is still recovering from his injuries.

"All of a sudden there was a slight crack and everything just gave way and all he knows he just tried to grab the guard rail and next thing he was sliding down trying to grab reo and he fell head first into the wet concrete, " he said.

ACT Roads spokesman Tony Gill says debris will need to be cleared away before the road can reopen.

"Our initial advice is that it could take up to two weeks before we are in a position to remove the debris and get the road open for public use," he said.

"We are getting an independent engineer's report just to get an understanding of how the bridge collapsed and secondly we need to engage a demolition contractor to remove the debris.

"But we also have to make sure it is safe for that demolition contractor to go in and remove the debris."

There is expected to be traffic delays over the next fortnight while the Highway is closed.