Kath Clarke, who runs the renowned sauna with her daughter Jenni, has launched an online petition calling for a change in the law to allow sex work to be carried out legally.
The petition, which has been signed nearly 1,000 times, calls on Sheffield City Council to make Sheffield ‘a pioneer of change’.
Kath said: “The current prostitution laws are harming, not helping, women all across the country.
“Every day sex workers have to put themselves in danger to avoid a criminal record, they can’t work together to keep each other safe, they can't look for a safe working environment in a parlour, they can't rely on the authorities for protection.
“Most sex workers are mothers supporting their families, struggling to make ends meet.
“Let’s help not judge or hurt them. Decriminalise all sex work now and make Sheffield a pioneer of change.”
The petition, launched two years ago, features on City Sauna’s website.
Despite brothels being illegal, City Sauna has allowed TV cameras onto its premises for documentaries over the years which laid bare the realities of what happen in some saunas and massage parlours.
In 2017, then Chief Inspector Richard Lambert, of South Yorkshire Police, said: "Where clear information is available that any premises is operating purely as a brothel, then that location is visited and thoroughly examined by officers and wherever possible, other partnership agencies.
“The primary concern of these investigations is first and foremost the safety and well-being of any individual at those locations given the risks of exploitation or abuse often associated with them.
“Once any safeguarding issues or other vulnerabilities have been established and taken care of, if there is any suggestion of criminality that will be addressed where appropriate and where evidence allows.
“There are a number of lawfully registered businesses that operate in the city as massage parlours or saunas. These are subjected to occasional formal visits by authorities and where there is credible evidence that offences are being committed, it is collected and reviewed. This includes offences against the Sexual Offences Act 2003.
“Specific intelligence that is received in relation to the commission of criminal offences at such a business is also a trigger for such a visit.
“It is recognised that on occasion an individual premises may contravene the law and where that occurs, proportional and specific action is taken at that location to address any issues that may be present. Again, this is conducted with the protection of the safety and wellbeing and any vulnerable or exploited persons that may be at that premises as the key priority.
“The overt running of any of these businesses as 'brothels' is not something that South Yorkshire Police accepts and appropriate steps would be taken if this were found to be the case.”
City Sauna has since moved premises since the documentaries and is now based on Attercliffe Road.
It opens seven days a week.