A Long Island woman collapsed and died in a Bay Shore health club’s bathroom because a male employee refused to enter the women’s locker room to try to save her, a lawsuit claims.

Emily Hamlin, 22, was in a ladies’-room stall at Planet Fitness on Route 27 during an early-morning workout when another gym member heard her drop to the floor, the legal papers say.

“I heard [a] flush, then a thud,” the member, Stephanie Dick, recalled in a sworn affidavit about the February 2012 incident. “I saw a woman’s arm drop to the floor, followed immediately by a loud snoring sound.”

Dick said she dashed to the front desk and pleaded with gym employee Sean Higgins to help.

“He said he didn’t know what to do and that he wasn’t allowed to go into the ladies’ bathroom,” Dick said in her sworn affidavit.

As Hamlin lay dying, Higgins remained frozen and was “scared and confused and didn’t know what to do,” Dick said.

“He said he was the only one working there and that a girl was expected to come in, but he didn’t know when she would be there.”

Dick’s statement is part of a wrongful-death suit Hamlin’s family is set to file in Suffolk County Supreme Court this week against the gym owners and Higgins.

“I want to know why no one helped her!” Hamlin’s mother, Jeanine, 52, said tearfully last week in her Central Islip home.

“He could have simply called 911! It’s baffling to me.”

Video footage from the gym obtained by Hamlin family lawyer Scott Charnas shows Hamlin entering the locker room at 5:08 a.m. Nine minutes later, Dick is seen at the front desk, imploring Higgins.

Dick said that, getting nowhere, she ran back to Hamlin and pounded on her locked stall door. Another gym member heard and ran out to the front desk.

“She was yelling at Sean to call 911,” Dick recalled.

Video shows the second member waving her arms and pointing to the bathroom at 5:21 a.m. Higgins, at one point, is seen idly looking at a computer screen.

Higgins picked up the phone to dial 911 4 1/2 minutes after learning of Hamlin’s collapse, the video’s time stamp shows.

As Dick talked to the 911 operator via cellphone — eight minutes after members alerted the front desk — another Planet Fitness employee, Kristin Smith, showed up in the locker room and “immediately” checked Hamlin’s pulse, finding it “weak,” the lawyer says.

Smith knows CPR but didn’t perform it, Charnas alleged.

Police arrived at 5:28 a.m. Hamlin was pronounced dead at 6:03 a.m.

The 24-hour gym, which boasts more than 500 members, is required by law to have an automated external defibrillator at all times and at least one person with certification to operate it.

Hamlin’s gym had neither, Charnas alleged.

A Planet Fitness lawyer sent a letter to Charnas saying the gym is not liable for Hamlin’s death.

“The safety of our members is extremely important,” spokeswoman McCall Gosselin said, noting the company can’t comment further until it has a copy of the suit.

Hamlin’s mom, meanwhile, said the gym must change its policies.

“No dollar amount will bring my daughter back,” she said.