Hyperbaric chamber explosion: Ex-safety officer's 'arrogance' led to death of 5-year-old boy
Sentencing in 2025 hyperbaric chamber explosion that killed boy
The safety officer at the Oxford Center, Gary Mosteller, pleaded to involuntary manslaughter in the explosion and fire that killed 5-year-old Thomas Cooper.
FOX 2 - The ex-safety officer at the Oxford Center in Troy was sentenced Monday for his role in the 2025 fatal explosion and fire that killed a young boy.
The backstory:
Gary Mosteller pleaded guilty to involuntary manslaughter in the accident that killed 5-year-old Thomas Cooper, and learned his fate Monday.
Mosteller was sentenced to 19 months to 15 years in prison for what Judge Kwame called "arrogance" in not following national safety laws.
"This arrogance, that's what this is, this 'I think I know better than the national fire code, I think I know better than my own training and experience," the judge said. "I agree with your attorney that this was put in place before you had returned to the center. But when you, as the safety director, the person in charge of everyone's safety, returned to the center, it is incumbent upon you, to say something."
In a prior hearing, the prosecution revealed a grounding strap used for the chamber was found in a "junk drawer" at the center.
A grounding strap would have grounded Cooper and likely would have prevented the static spark that caused the fire and explosion which killed Cooper and severely injured his mother.
‘Mr. Mosteller is not a violent man’
The other side:
Defense attorney Alona Sharon spoke for Mosteller, who opted not to speak in court due to an ongoing civil case.
Sharon spoke of Mosteller's frequent treatments of Cooper that he oversaw and the relationship between the two.
"He's 66 years old, standing before this court with no criminal history," she said. "He is, your honor, someone who made a horrific mistake in this case. It caused a tremendous loss for this family. He understands the devastating nature of what happened and of his mistake and lapse in judgment."
The Oxford Center provided therapy for adults and children with health conditions like autism, ADHD, and autoimmune diseases, through Hyperbaric Oxygen Therapy.
Assistant Attorney General Chris Kessel oversaw the prosecution.
"The real world consequence of (Mosteller and staff knowing better) was that a 5-year-old boy whose life hadn't even started, burned alive while his mother watched," he said.
‘Mr. Mosteller has to be punished’
Judge Rowe said that although Mosteller did not intend to kill Cooper, he played a major role in creating the fatal situation.
The sentence is not meant to rehabilitate Mosteller, but to serve as a public and private deterrence, he said.
"There are folks all across the state of Michigan operating these hyperbaric chambers, and I would hope that this case serves as an example of the need to follow safety protocols," he said. "Mr. Mosteller, according to his criminal history, has never even gone to jail. And so I know that prison is going to be an eye-opening experience for him."
What's next:
Tamela Peterson, left, Gary Marken, Jeffrey Mosteller and Aleta Moffitt.
Still facing charges are Oxford CEO Tamela Peterson and management assistant Gary Marken for second-degree murder as well as employee Aleta Moffitt.
Their hearings remain ongoing.
The Source: Information for this report is from previous coverage and today's sentencing.