The operating hours of Sydney's $2.9 billion light rail should be extended beyond 1am once the city's lockout laws are scrapped to avoid a "powder keg" emerging when bars and clubs close, a union for health workers says.
The long-awaited CBD and South East light rail project will open to the public on Saturday.
It comes a month before the controversial lockout laws, introduced to the CBD in 2014 after the deaths of one-punch victims Thomas Kelly and Daniel Christie, will be wound back in the new year everywhere except Kings Cross.
The changes - announced by NSW Premier Gladys Berejiklian in November - will also remove restrictions on serving cocktails, shots and drinks in glasses after midnight and remove the 10pm curfew on bottle shop opening hours.
A 3.30am last drinks curfew will also be implemented - a 30-minute extension that went against the 3.00am curfew recommended by doctors.
Regular services on the CBD and South East Light Rail will run from 5am to 1am every day, a decision which the Health Services Union - which is opposed to lifting the lockouts - is now calling for Transport Minister Andrew Constance to reconsider.
In a letter sent to Mr Constance on Sunday, HSU secretary Gerard Hayes says the lack of public transport between 1am and 5am was a "significant contributing factor to violence in Kings Cross" in the period before the lockout laws.
"This created a powder keg of alcohol and testosterone, often leading to violence," Mr Hayes said.
"I am deeply concerned a similar powder keg will now emerge in the CBD and Oxford Street, as bar and pub patrons filter out onto the street without readily available public transport.
"Our members in emergency departments and ambulance have lived the reality of alcohol-fueled violence. It is ugly and dangerous.
"No health or emergency service worker deserves to be used as a punching bag. Many of our members are rightly anxious of what awaits them when the lockouts are lifted."
While the union remains "steadfastly opposed" to the relaxation of the lockout laws, Mr Hayes urged the transport minister to expand the light rail's hours of operation to "swiftly move people out of alcohol-drenched precincts and improve public safety."
"Among the justifications for lifting the lockout laws is the argument that Sydney needs to be a "24-hour city". Personally, I think this argument is arrant nonsense," Mr Hayes said.
"But if we are to have a 24-hour drinking culture, surely we must also have 24 hour public transport."
In a statement on Sunday evening, Mr Constance said the government will be "assessing demand requirements across all modes of transport across all hours of the week".
"We will pay particular attention to the changes in requirements because of the night-time economy."
NSW Labor's transport spokesman Chris Minns said prior to the lockouts Sydney's city, especially in Kings Cross, "filled up like a bathtub with young people who couldn't escape after a certain time".
"I remember as a young person myself there was just really no way out of the city or the Cross after one o'clock until the trains started again about 6am," Mr Minns told AAP on Sunday.
"Twenty four-hour transport, particularly out of busy hubs around the city, is the only way for big cities to work because you get that flow of people in and out, and it's just safer."
He called on the government to consider the union's proposal, especially over the Christmas period.
The light rail could run 24-hours on Friday nights and weekends as a first step, and could then expand depending on how Sydney grows and how busy the night-time economy becomes in the city, Mr Minns said.
Australian Associated Press