OAKLAND COUNTY, Mich. – Prosecutors said a safety manager at the Oxford Center conducted “his own experiments” on a hyperbaric chamber to prove to employees it was safe prior to a deadly explosion that killed a 5-year-old boy.
Thomas Cooper, 5, was killed on Friday, Jan. 31, 2025, when the hyperbaric chamber he was receiving treatment in at the Oxford Center in Troy exploded. Cooper’s mother was also injured.
Cooper’s family has retained representation with Fieger Law. A lawsuit has not yet been filed, but their attorney said they filed a motion for injunctive relief so the firm’s team can enter the building where the explosion happened and conduct their own inspection.
Oxford Center founder and CEO Tamela Peterson, Oxford Center safety manager Jeffrey Mosteller, and Oxford Center primary management assistant Gary Marken are all facing second-degree murder and involuntary manslaughter charges.
A fourth employee, Aleta Moffitt, has been charged with involuntary manslaughter and placing false information on a medical chart.
All four individuals were arraigned on Tuesday, March 11, 2025.
---> Read more: 4 employees arraigned after 5-year-old boy killed in Oakland County hyperbaric chamber explosion
Safety manager ‘was conducting his own experiments’
During Jeffrey Mosteller’s arraignment, assistant attorney general Chris Kessel alleged that Mosteller “was conducting his own experiments” on the hyperbaric chamber.
“This defendant was the, for lack of a better phrase, safety officer, at the Oxford Center. Which is something considering the way this facility was being operated, and the court is aware multiple safeguards were being disregarded, knowingly,” Kessel said.
Kessel said Mosteller was conducting experiments on the chamber to prove it was safe.
“The investigation showed that this defendant was conducting his own experiments to try and prove the safety, as it relates to this particular chamber. You know, obviously, these were his own experiments, none of which were actually recognized by any scientific body. They were not peer reviewed. The people’s position is they were just designed to hide the actual safeguards that were being disregarded,” Kessel said. “These experiments were meant to show the under employees that what they were doing was safe because ‘look at these experiments that he conducted.’”
Magistrate Elizabeth Chiappelli said she found what the prosecutor indicated to be “frightening” and that the explosion was preventable.
“What the prosecutor’s just indicated to me is frightening. That safeguards were not utilized, experiments were done to show employees, lead them down a wrong path, which means we’re safe, when obviously they were not,” Chiappelli said. “This could have been prevented if proper protocols were followed. I can’t get over that. That that form of judgment was utilized. And if that’s the form of judgment that you’re utilizing in your life, I have some concerns about you and your ability to participate in the criminal process going forward.”
Mosteller had been employed full time at the Oxford Center in Brighton since July 2019 and worked as a safety director and educator. He reported that he had obtained an associate’s degree in underwater technology.
Chiappelli set Mosteller’s bond at $250,000 cash/surety bond, no 10%.
---> Find full coverage of this case here.
What is hyperbaric oxygen therapy?
Hyperbaric oxygen therapy involves breathing 100% pure oxygen.
During a hyperbaric oxygen therapy (HBOT) session, a patient is placed in a hyperbaric chamber and the air pressure inside is raised to a level that is higher than normal air pressure, according to the FDA.
The increased air pressure helps the lungs collect more oxygen, getting more oxygen to the tissues that need it. The treatment can help the body heal and fight certain infections.
The FDA notes that too much oxygen can cause damage to the body. Because of this, the FDA regulates both the oxygen used in HBOT and the hyperbaric chambers.
Risks of hyperbaric oxygen therapy
HBOT is considered generally safe. The FDA said that serious complications are rare when chambers are used for treatment cleared by the FDA.
Here is the FDA’s list of potential risks:
- Ear and sinus pain
- Middle ear injuries, including tympanic membrane rupture
- Temporary vision changes
- Lung collapse (rare)
The FDA noted that because of the high concentrations of oxygen, there is a risk of fire. The risk of fire is “one reason why the FDA recommends treatment at an accredited facility.”
---> Read more: Hyperbaric chambers: What they are, what they treat, risks, and accreditation
