Key facts
- Former safety manager Jeffrey Mosteller was sentenced to 19 months in prison.
- The sentence is for his role in the 2025 death of five-year-old Thomas Cooper.
- Cooper died in a fire and explosion inside a hyperbaric oxygen chamber at the Oxford Center.
- Mosteller pleaded no contest to involuntary manslaughter.
- Other Oxford Center employees face charges including second-degree murder.
Jeffrey Mosteller, 66, has been sentenced to one year and seven months in prison after pleading no contest to involuntary manslaughter in connection with the January 2025 death of five-year-old Thomas Cooper. Cooper died in a fire and explosion inside a hyperbaric oxygen chamber at the Oxford Center, an alternative healthcare facility where Mosteller worked as a safety manager.
According to an expert, the child pulled a sheet off a mattress, creating a static electricity spark that ignited a flash fire in the oxygen-rich environment, killing him within seconds. Cooper's mother sustained burns while attempting to rescue him.
Mosteller is one of four former Oxford Center employees facing charges. Tamela Peterson, the founder and CEO, is charged with second-degree murder. Facility manager Gary Marken faces charges of second-degree murder and involuntary manslaughter, while operator Aleta Moffitt is charged with involuntary manslaughter and falsifying medical records.
The Oxford Center used hyperbaric oxygen therapy, which the FDA has cleared for 13 disorders. However, the safety of these chambers has become a point of controversy, with some figures associated with the Trump administration health secretary Robert F Kennedy Jr endorsing the therapy while others express skepticism.
Cooper's parents have filed a $100 million wrongful death lawsuit against the clinic and the chamber's manufacturer.