A New Jersey woman has sued the Chester County addiction rehab facility where her 29-year-old son fatally overdosed two days after arriving last fall, according to court documents.

Christine Vernile of Sewell wrote in the suit that son Joel overdosed on fentanyl in his room at Recovery Centers of America’s Devon location on Oct. 5, and asked for compensatory and punitive damages for negligence and wrongful death.

The suit alleges that RCA staffers did not properly supervise Joel Vernile during his stay at the center or clean his room thoroughly before he arrived, and that he overdosed on drugs believed to have been left in the room by a previous occupant.

Vernile arrived at RCA on Oct. 3 to participate in its “24/7 Medically Supervised Detox” program. He had struggled with opioid addiction for some time, and had been living in a recovery home when he relapsed and entered the program. It was his 10th course of addiction treatment, according to the suit.

He was last seen by staffers just before 2 p.m. on Oct. 5, the lawsuit alleges, when they gave him medication to help him through withdrawal symptoms. About a half-hour later, he was found unresponsive in his room, according to the suit.

Police who searched his room found two empty packets that had contained opioids, according to the suit. They also found another packet, still full, on the nightstand in Vernile’s room, wrapped inside a manila tag labeled with the name of the room’s previous occupant.

The suit alleges that the person who stayed in Vernile’s room before him — who had left just a few hours before Vernile was admitted to RCA — had left drugs in the room, and that Vernile found them and overdosed.

“Employees who cleaned the detox room failed to perform their most basic function, which was to ensure that the room was free of drugs,” the suit says.

An RCA spokesperson declined to comment on the suit “due to pending litigation.” Vernile’s family also declined further comment through lawyer Jordan Schlossberg of Astor Weiss Kaplan & Mandel.

“Facilities which treat individuals with substance abuse problems are required to provide adequate and proper safeguards during the recovery process, including monitoring and supervision," said Schlossberg. “A recovery center which fails to protect these vulnerable individuals must be held accountable. Joel Vernile’s death during his stay at Recovery Centers of America at Devon was not only preventable, it was the very same tragedy which RCA was required to protect against.”