Most indoor tanning salons comply with Texas’ tanning ban for those under 18, new research suggests.

When female employees of a mystery shopping firm called posing as 17-year-olds interested in tanning, 81 percent of indoor tanning facilities complied with the Texas ban on indoor tanning for those under the age of 18, according to a study conducted by The University of Texas MD Anderson Cancer Center.

Upon discovering the caller’s age, employees at those facilities told the caller she could not use indoor tanning, even with the permission of her parents.

“This level of compliance with the under-18 ban enacted by the Texas Legislature in 2013 underscores the importance of this approach as a strategy for skin cancer prevention,” says study author Mary Tripp, Ph.D., instructor in Behavioral Science, in a news release. The study appears as a letter to JAMA Dermatology.

Researchers identified 829 tanning facilities in Texas to contact in July and August of 2015. Of these, 635 could be reached by the mystery shopping firm callers; 445 were free-standing indoor tanning establishments, 133 were beauty salons or spas and 57 were other retail businesses that housed a tanning device.

Of the 635 surveyed, 512 provided responses that complied with the ban and 120 did not, with the most common non-compliant responses indicating the shoppers could tan with a note from their parents or accompanied by a parent. Free-standing centers (86 percent) were most likely to comply, with beauty salons/spas (68 percent) least likely.

More than 80 percent of facilities told callers their clients could tan daily, in contrast to a schedule of three or fewer sessions during the first week recommended by the U.S. Food and Drug Administration. The vast majority of facilities responded directly (68 percent) or indirectly (25 percent) that a burn is possible with indoor tanning.