A UC Berkeley graduate who was severely burned after spilling hot coffee on her lap filed a lawsuit Thursday against In-N-Out Burger claiming employees in Oakland refused to call an ambulance.

Hedy Chen claims employees at the drive-through restaurant ignored her screams and repeated requests to call 911. Instead, she was given a pack of ice, which can exacerbate scarring, according to the suit filed in Alameda County Superior Court.

"What they were supposed to do was call 911 because the operators know that" ice is bad, said Kirk Boyd, her lawyer. "They said there is a policy of not calling 911. That policy violates their duty of care to customers."

Arnie Wensinger, the executive vice president for the Irvine-based chain, said he couldn't comment on the lawsuit. "However, all In-N-Out Burger associates are authorized to assist our customers and to call 911 in emergency situations," he told the Chronicle in an e-mail.

The case is reminiscent of a notorious 1992 case in which a New Mexico woman won a $2.7 million judgment against McDonald's after she was burned by coffee.

The Oakland incident occurred April 1, 2013, after Chen, who was a business student at UC Berkeley, picked up a friend at Oakland International Airport. It was around 10 p.m. when the two friends decided to stop at the In-N-Out drive-through window at 8300 Oakport St. in Oakland for coffee and a sandwich.

The suit alleges that the employee handed Chen, who was wearing shorts, an "excessively hot" paper cup with no protective sleeve.

"It's just scalding," Boyd said. "She took it in her hand, but it was so hot she couldn't hold onto it."

The coffee spilled onto Chen's thighs and lap. The pain caused her to scream "call 911, call 911," Boyd said.

The worker refused, citing company policy. Employees finally handed her a bag of ice and told her to move her car out of the way despite her continued screams for help, Boyd said,

"Ice is a bad thing to give for burns. It exacerbates the wound and the scarring," Boyd said. Meanwhile, "she's got second-degree burns and all they are worried about is her moving her car so they could get to the next person in line."

Chen, whose friend eventually called 911, was treated for three days at the Bothin Burn Center at Saint Francis Memorial Hospital in San Francisco.

"It was second-degree burns," Boyd said. "She still has scars to this day."

Boyd said the case is similar to the 1992 case involving 79-year-old Stella Liebeck, of Albuquerque, N.M., who was severely burned by McDonalds' coffee served in a Styrofoam cup while she was sitting in the passenger seat of her grandson's car. Liebeck won a settlement after she showed the coffee was excessively hot.

"The carryover from that other case is that coffee can cause severe burns. That woman really was severely burned," Boyd said. "In this case, she didn't spill it on herself. It was too hot to hold. Regardless of how that coffee spilled, though, if a customer is badly burned and they ask you to call 911 it is your legal duty to call 911."

Chen, who graduated from UC Berkeley two months later, is seeking unspecified damages for her injuries.