A curious, energetic, smart, outgoing and thoughtful little boy.

That’s how family, friends and teachers say they will remember 5-year-old Thomas Cooper who tragically died inside a hyperbaric chamber at a medical facility in Troy, Michigan, last month.

The descriptions form part of a heartfelt obituary written about Cooper ahead of a memorial visitation held on Thursday, about two weeks after he died. 

Cooper was receiving treatment inside a chamber, a pressurized container containing 100% oxygen, when it suddenly exploded at The Oxford Center at 165 Kirts Blvd.

Thomas Cooper died when the chamber he was inside exploded in Michigan. He is being remembered as a “curious, energetic, smart, outgoing and thoughtful little boy.” (Family of Thomas Cooper)

The chambers are used to provide Hyperbaric oxygen therapy (HBOT) and a typical chamber can hold one person. It requires the patient to lie down in the tube-shaped device that looks like an MRI machine and breathe the oxygen. A hyperbaric chamber contains up to three times the amount of oxygen than a normal room.

Harrington said the boy’s parents were hopeful the services would improve his quality of life. 

“This wasn’t some type of lifesaving measure that was absolutely needed,” Harrington told the outlet. “It was just a mother who was trying to help her son with some conditions that he had and was promised that with these conditions and this treatment, that they would be able to help.”

“Annie was trying to help her child as any parent would — as good parents do.”

Harrington, who is a managing partner of Fieger Law in Southfield, Michigan, said the boy had received multiple sessions of hyperbaric oxygen therapy at the center before tragedy struck.

It’s unclear what caused the chamber to explode. The family intends on filing a lawsuit to prevent a similar incident from taking place again, Harrington said, adding that the boy’s parents are “absolutely devastated.”

The obituary also mentions that Cooper loved to make art and was constantly curious about the world around him and liked to know how things worked.

“At night, he liked to listen to audiobooks as he tried to go to sleep, with some of his favorites being Yoto Daily, Charlie and the Chocolate Factory, and James and the Giant Peach,” the obituary reads.

Cooper, who was in preschool, was always on the move and loved looking out for his younger brother, who was his best friend, according to the obituary. (Family of Thomas Cooper)

As well as being used to tackle sleep apnea and attention-deficit/hyperactivity disorder, the devices are also used to treat a variety of other health problems, including carbon monoxide poisoning, diabetic foot ulcers, anemia, infection of the skin and bone and vision loss.

Such devices require FDA clearance to ensure that they are approved to be used as intended and are safe and effective.

HBOY is also well known for treating scuba and deep-sea divers affected by the rapid change in pressure around them, according to the FDA. 

In a statement to the Detroit Free Press immediately after the incident, The Oxford Center spokesperson Andrew Kistner wrote that the cause of the explosion is unknown.

“As law enforcement officials have shared, at our location in Troy, Michigan this morning, a fire started inside of a hyperbaric oxygen chamber. The child being treated in that chamber did not survive and the child’s mother was injured,” the statement reads.

“The safety and wellbeing of the children we serve is our highest priority. Nothing like this has happened in our more than 15 years of providing this type of therapy. We… will participate in all of the investigations that now need to take place.”

The location is temporarily closed while authorities investigate the deadly incident, NBC Washington reported. No charges have been filed, per the outlet citing police. 

In May 2009, an explosion of a pressurized oxygen chamber killed a 4-year-old and his 62-year-old grandmother. Authorities said a blast dislodged a tube attached to the hyperbaric chamber, which resulted in an explosion and flash fire, according to CBS.