Willie Mae Truesdale was startled by a loud explosion coming from her kitchen. When she went to check, she found her glass oven door shattered all over the floor. “It was shocking and you had to really see it to believe it,” she said. “It was like, what in the world?

Glass shattered, glass was out here on the floor.” The weirdest part? Her oven wasn’t even on at the time. And Willie Mae isn’t the only one who’s had this happen.

The Curious Case of Exploding Glass Oven Doors

Cheryl, a suburban mom, had a similar shock during the COVID-19 quarantine. She tried baking brownies, but they came out soggy in the middle. Her oven, just three months old, was 25 degrees off. After quarantine, she called a professional to fix it. But first, she ran the self-cleaning cycle. Towards the end, there was a loud explosion, and the inner glass of the oven door shattered inside.

Michelle Wheat’s oven door explosion left glass all over her kitchen. Her three-year-old oven wasn’t on at the time either. Luckily, none of her four young children were hurt. Like Truesdale, her oven was from Frigidaire. Cheryl’s was Bosch, but other brands have had similar issues. Since 2019, the Consumer Product Safety Commission has received about 450 reports of exploding glass oven doors.

All three women faced difficulties with the manufacturers afterward. Truesdale’s oven was still under warranty, but Frigidaire’s technician blamed the family for the explosion, even though the oven was off. She had to pay for a new door herself. Luckily, Bosch replaced Cheryl’s oven after NBC got involved.

Wheat’s oven was out of warranty. She paid a technician $100 to tell her the glass was broken and needed replacing, costing another $314. Frigidaire suggested she buy an extended warranty in case it happened again. “This should not have happened,” said the frustrated mom. “That was the point I was trying to make to them.”

What Causes Oven Doors to Shatter?

“There are two scenarios for why oven glass can break spontaneously,” says Mark Meshulam, the Chicago Window Expert. “One type of oven glass is soda lime glass, similar to window glass. It’s tempered by rapid heating and cooling, which makes it more prone to breaking.

The other type is borosilicate glass, used in lab glassware and old-time Pyrex. It handles heat and cold better. The shift to soda lime glass has increased these breaks because it’s less tolerant of thermal cycles.”

Another likely cause is a nickel sulfide inclusion, a tiny flaw in the glass. “It’s only about a tenth of a millimeter in diameter. Over time, it fights to get out. Sometimes, a high heat event like oven cleaning can cause that spontaneous failure,” Meshulam explained.

Meshulam reassures that the self-cleaning feature is safe. “Most people will use it their whole lives without encountering this problem,” he said. He also believes microscopic chips and flaws cause ovens to explode even when off. The door can shatter long after the initial damage occurs.

Prevention Tips

Tiny points of damage can happen during production, shipping, or installation, which are beyond homeowners’ control. However, some habits can avoid damage at home. Aggressive cleaning techniques and too much physical impact can put microscopic scratches or chips on the glass.

So, while Willie Mae’s story and others like it are alarming, knowing the causes and how to prevent them can help keep your kitchen safe. If you’ve had a similar experience, share your story in the comments.