4 To Stand Trial In Fatal Oakland County Hyperbaric Chamber Blast

TROY, MI — The owner and three employees of an Oakland County medical center where a 5-year-old boy died in a hyperbaric chamber explosion will stand trial, the Michigan Attorney General's Office said Tuesday.

In January 2025, officials said 5-year-old Thomas Cooper was inside a hyperbaric chamber that exploded while receiving treatment at the Oxford Center in Troy.

The boy's mom, who was standing next to the chamber, was also injured in the explosion, according to police.

Oxford Center Owner Tamela Peterson, 58, of Brighton; Safety Manager Jeffrey Mosteller, 64, of Clinton Township; and Assistant Gary Marken, 65, of Spring Arbor, were each charged with one count of second-degree murder (up to life-felony) and an alternative count of involuntary manslaughter (15-year felony) in connection with the incident.

The alternative manslaughter charge means that a jury will decide which charge accurately fits their conduct.

Aleta Moffitt, 60, of Rochester Hills, the operator of the hyperbaric chamber, was charged with one count of involuntary manslaughter (15-year felony) and one count of medical records – intentionally placing false information on a chart (four-year felony).

Peterson has also been charged with nine counts of health care fraud, each punishable by a maximum of four years in prison and/or a $50,000 fine.

A pretrial date has not been set.

"When professionals entrusted with the care of our children abandon the standards meant to keep them safe, they must be held accountable," Michigan Attorney General Dana Nessel said. "I am relieved that this case will proceed to trial, where we will continue to pursue justice for Thomas and his family."

Investigators believe a single spark caused the explosion.

Prosecutors argue more safety steps could have prevented the tragedy, such as using grounding straps to prevent sparks. They said other safety protocols from the National Fire Protection Association (NFPA) and Sechrist (the manufacturer of the hyperbaric chamber) were ignored.

Moreover, prosecutors said the medical facility's officials ignored daily maintenance checks and annual safety inspections. They said there was also no medical doctor or safety supervisor on site when Cooper was undergoing treatment, which was being performed by a non-licensed technician.

A lawyer representing the family told NBC News the boy was being treated for sleep apnea and attention-deficit/hyperactivity disorder. Prosecutors said those conditions are not approved to be treated with hyperbaric oxygen therapy.