Oxford Center Employee Pleads No Contest in Hyperbaric Chamber DeathJuly 21, 2026Nik Rajkovic / news@whmi.comOne of four people charged in the deadly hyperbaric chamber explosion at the Oxford Center in Troy has pleaded no contest to a lesser charge. Safety Director Jeffrey Mosteller pleaded no contest Tuesday to involuntary manslaughter, dismissing an additional charge of second-degree murder, according to the Michigan Attorney General's Office. Three other defendants — Oxford Center CEO Tamela Peterson, operations manager Gary Marken and chamber operator Aleta Moffitt — are still awaiting trial. All of them charged after a 5-year-old boy was killed while undergoing treatment inside a hyperbaric chamber which caught fire in January 2025. A former employee has testified Oxford Center workers ignored safety protocols by not using grounding straps during hyperbaric treatment.