The source of the smell that was initially suspected to be a gas leak, turned out to be a decomposing battery in a piece of cleaning equipment in a storage cupboard.
Hazmat crews have isolated the source of the issue and rectified it.
Occupants of the building are new being allowed to return.
ACT Fire & Rescue is currently investigating a suspected gas leak in Bruce.
Crews were alerted to the incident on Eastern Valley Way at 8.55am and responded with two fire pumpers, breathing apparatus support and a hazmat unit.
Approximately 100 people have been evacuated from the building and firefighters are investigating the cause.
Firefighters are investigating the discovery of chemicals in a filing cabinet discarded on Tennant Street in Fyshwick.
ACT Fire & Rescue was called to the incident at 1:30pm.
The hazardous materials unit, breathing apparatus van, a pumper and a commander are on scene.
Firefighters are conducting several tests to identify the substance.
There is no threat to surrounding businesses.
Three people have been transported to the Canberra Hospital following a two-car crash in Farrer.
The ACT Ambulance Service responded to the incident on Yamba Drive near Dookie Street at 8:50pm.
A 50-year-old man and 41-year-old woman sustained upper body injuries, and were transported to the Canberra Hospital in a stable condition.
The driver of the other car, a 25-year-old woman also sustained upper body injuries and is in a stable condition after being assessed by intensive care paramedics.