Jeffrey Mosteller, a 66-year-old former safety manager at the Oxford Center in Michigan, has been sentenced to 19 months in prison for his role in the death of five-year-old Thomas Cooper, who was killed in a hyperbaric oxygen chamber fire in January 2025. Mosteller had pleaded no contest to involuntary manslaughter and faced up to 15 years in prison. The incident occurred while Cooper was undergoing treatment for ADHD and sleep apnea at the center, where an expert determined that static electricity from the child's movement caused a spark that ignited a flash fire. This is one of several charges brought against Oxford Center employees in connection with Cooper's death.
Written by the local model on 2026-09-04,
using this article's own text rather than the other coverage of the
same event (that is the story summary below).
Story summary
Jeffrey Mosteller, the 66-year-old safety manager at the Oxford Center in Michigan, was sentenced to 19 months in prison for his role in the death of 5-year-old Thomas Cooper. The boy died in January 2025 after a hyperbaric oxygen chamber caught fire and exploded while he was undergoing treatment for sleep apnea and attention-deficit/hyperactivity disorder (ADHD) at the center, which uses alternative health care methods to treat children with various conditions, including autism and autoimmune diseases. Cooper's mother had rushed towards the chamber when it caught fire, but was unable to save her son. Mosteller pleaded no contest to involuntary manslaughter, avoiding a maximum sentence of 15 years in prison.
Written for “Hyperbaric Chamber Fire Trial” on 2026-09-05,
grounded in this article and the 1 other(s) covering the same event.
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Leaning score -0.35 for article 3912 (high confidence, 1 verified quote) · logged 2026-09-04
A former safety manager has been sentenced to one year and seven months in prison in connection with the death of a five-year-old Michigan boy who was killed in a fiery January 2025 explosion inside a hyperbaric oxygen chamber.
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who → sentence → chamber
Jeffrey Mosteller, 66, received that sentence after pleading no contest to involuntary manslaughter in Oakland county circuit court in Michigan on Monday.
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Mosteller → receive → Monday
He worked as the safety manager at the Oxford Center, an alternative healthcare facility that treats children with a range of health conditions – including autism, ADHD and autoimmune diseases – using hyperbaric oxygen therapy.
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that → work → therapy
Mosteller faced up to 15 years in prison before being handed his 19-month sentence.
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Mosteller → face → sentence
Five-year-old Thomas Cooper, of Royal Oak, Michigan, was undergoing treatment for attention deficit hyperactivity disorder (ADHD) and sleep apnea at the Oxford Center in the Detroit suburb of Troy when a fire erupted inside the hyperbaric chamber.
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fire → undergo → chamber
That triggered an explosion which killed Cooper.
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which → trigger → Cooper
According to an expert who viewed video of the case, the child had squirmed enough to pull the sheet off a mattress inside the chamber, causing a spark of static electricity.
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child → accord → electricity
That spark became a flash fire that incinerated him within seconds because of the oxygen-rich environment surrounding him.
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that → become → him
Cooper’s mother was badly burned on her arms and chest while desperately trying to open the tank.
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mother → burn → tank
Mosteller is one of four former Oxford Center employees charged in connection with Thomas’s death.
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Mosteller → charge → death
The other three were still awaiting trial at the time of his sentence.
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three → await → sentence
The Oxford Center founder and chief executive, Tamela Peterson, 58, was charged with second-degree murder.
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founder → charge → murder
Facility manager Gary Marken, 65, was charged with second-degree murder and involuntary manslaughter.
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Marken → charge → murder
And Aleta Moffitt, 60, who was operating the chamber when it exploded, was charged with involuntary manslaughter and intentionally placing false medical information on a medical records chart.
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it → operate → chart
The US Food and Drug Administration (FDA) has cleared hyperbaric chambers to be marketed as safe and effective for 13 disorders, including severe burns, decompression sickness and non-healing wounds.
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chambers → clear → burns
The therapy works by delivering pure oxygen to a person’s body inside a pressurized chamber.
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therapy → work → chamber
Despite its FDA approval in certain cases, hyperbaric oxygen therapy (HBOT) has been a growing source of controversy as the safety of these chambers have been called into question.
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safety → grow → question
Many allies of Trump administration health secretary Robert F Kennedy Jr have endorsed HBOT, but many others have expressed skepticism towards the treatment’s increasing push into the healthcare mainstream.
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others → endorse → mainstream
Cooper’s parents filed a $100m wrongful death lawsuit against the clinic and the chamber’s manufacturer over their son’s death.
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parents → file → death
