Solariums will have to display signs warning of the danger of skin cancer following a Federal Court ruling.
Tanning salon operators could be jailed for contempt of court if they do not post the warnings, advising customers that solarium use has been linked to an increased risk of skin cancer.
The signs will also have to tell customers that tanning does not protect the skin from sunburn, that skin damage caused by ultraviolet light may not be repaired by the body's skin repair mechanisms, and that damage can be caused without sunburn.
The rulings are a victory for the family and friends of Melbourne woman Clare Oliver, 26, who died of skin cancer last year.
Ms Oliver believed her cancer was caused by her visits to solariums and used her dying months to warn against using them.
The Australian Competition and Consumer Commission (ACCC) took the Australian Tanning Association (ATA) and two companies - Body Bronze International Pty Ltd and Tropical Sun Industries Pty Ltd - to court for breaches of the Trade Practices Act.
The ACCC claimed the companies had engaged in false, misleading and deceptive conduct in relation to the promotion of solarium use.
Justice Ray Finkelstein granted injunctions restraining salons from making false and misleading claims about the safety of tanning.
He also ordered the ATA and tanning franchises to publish notices in salons and on websites warning that tanning damages skin.
ACCC chairman Graeme Samuel welcomed the ruling, and said it was notable given the health message that should be passed onto the Australian community.
Mr Samuel said the court declared that the companies did not reveal that the use of solariums would lead to an increased risk of skin cancer and skin damage.
The public needed to heed the court's ruling "very carefully and keep in mind that the court has declared them (the solarium claims) to be false or misleading," he said.