Full services resumed at Wesley hospital in Brisbane on Tuesday for the first time since an outbreak of legionnaires disease last month.
A man died and a woman was left critically ill during an outbreak of the disease in early June.
Chemicals were flushed through about 30km of piping at the site three times to clear Legionella bacteria from the hot water system.
The latest test results on the system returned all clear.
The ABC reports extra surgery is scheduled this weekend to try to work through a backlog of cases at the hospital, which has 500 beds.