Four nurses treated after breathing in gas at Liverpool Hospital
Four nurses have been treated at Liverpool Hospital in Sydney's south-west after inhaling gas in the emergency department.
The hospital enacted its emergency response plan after multiple reports of nurses feeling unwell just before 6am on Wednesday.
Fire and Rescue NSW arrived soon after to investigate an odour or vapour at the site. 
Zone Commander for Metropolitan South 3 Greg Wright this morning confirmed it was a gas the nurses had inhaled.
He said the gas was only in a "small part of the hospital" where patients are triaged when they arrive in ambulances.
Three patients who were in another area were relocated to be treated, but were unaffected.
A hazmat unit checked for potential gas leaks while looking for the source of the gas, initially thought to have come from an air conditioning unit.
"We've identified it came from a couple of basins … it probably is some sewerage gas," Zone Commander Wright said.
"We will be working with hospital engineering staff to resolve any issues here."
Fire and Rescue will also partner with police and ambulance services to reopen the ambulance bays.
The emergency department remained open throughout the operation. 
"It's a timely reminder that businesses should have an emergency plan and know what to do in case of these sort of situations," Zone Commander Wright said.
The situation is currently stable.
We acknowledge Aboriginal and Torres Strait Islander peoples as the First Australians and Traditional Custodians of the lands where we live, learn, and work.
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