A staff member who was working at the Swiss bar where a deadly fire broke out on New Year's Eve received no safety training and was unaware of the danger posed by the ceiling that caught alight, her family's lawyer has alleged.

Cyane Panine, 24, died in the fire at Le Constellation bar in Crans Montana and was widely identified in a video wearing a helmet and holding a champagne bottle with a sparkler attached when the ceiling caught fire.

The bar's French owners, Jacques and Jessica Moretti, have been accused by authorities of manslaughter by negligence, bodily harm by negligence and arson by negligence.

Forty people were killed and 116 were injured in the blaze in southwest Switzerland.

In a statement to the BBC, Sophie Haenni, the lawyer representing Panine's family, said she "wasn't supposed to be serving tables" on the night of the fire but had been asked to go downstairs to help manage high demand for bottles.

"Cyane simply followed the instructions given, did her job, and did so in front of the manager (Jessica Moretti)," Haenni said. "She was never informed of the ceiling's danger and received no safety training."

Haenni said that "if safety standards (particularly regarding materials) had been followed and the required inspections carried out," the casualties "could have been avoided," adding: "Cyane is undoubtedly a victim."

The statement from lawyers for Panine's family also says she "felt used" and was "suffering from her working conditions".

"She [Panine] expressed her incomprehension at the lack of empathy and understanding from her employers" in regards to her workload, the statement adds.

"My clients have lost their daughter, their sister. A loved one, a wonderful person, has been stolen from them," the statement says.

The BBC has contacted lawyers for Jacques and Jessica Moretti for a response.

On Wednesday, a Swiss court imposed a travel ban on Jessica Moretti as an alternative to pre-trial detention due to what prosecutors claim is a "risk of flight". She has had to surrender her passport and must report to police every day, authorities say.

She previously told reporters that she was sorry about the "unthinkable tragedy".

Jacques Moretti is being held in custody for an initial period of 90 days. Prosecutors have also argued that he is a flight risk.

Initial findings from the investigation into the blaze suggest that it was caused by sparklers igniting soundproof foaming that lined the ceiling.

Authorities have acknowledged that the bar in the popular ski resort had not undergone safety checks for five years.

The Swiss canton of Valais has now banned pyrotechnic devices in all indoor public venues.

Authorities said each of the victims would get a 10,000 franc ($12,500; £9,200) emergency payment, with a fund being set up to collect donations.