BOSTON (CBS) – A scar from 100 stitches is a constant reminder of how close Jana Kierstead came to losing her eight year old son Lane.
"Three minutes he lost a third of his blood volume," Jana says. "So it easily could have been a very different end."
While playing in their Needham home, Lane's arm went through a glass pane in a door severing a vein.
"It was a freak accident," she says. "It could have happened to anyone, anywhere."
It happened to Glen Bunchken.
The 69-year-old retired professor was meeting his wife for lunch at a Pittsburgh sub shop when he fell through the glass door. A piece of glass cut him right through the neck and he bled to death.
Both accidents were caused by annealed glass.
International glass safety expert Mark Meshulam demonstrated how annealed glass breaks, creating knife-like shards.
"Every few days there is an accident of this sort somewhere," says Meshulam.
Because of this danger, federal and state laws were changed in the 1970's requiring safety glass in all new buildings. Another option is laminated safety glass.
Butch Rosales of Stuart Glass in Brighton says the problem is that older homes and buildings are exempt and it's tough for homeowners to know which kind of glass they have.
Tempered glass is identified with a logo but laminated glass and annealed glass are not.
"There's no way of telling if it's annealed glass or not until it breaks," Rosales says.
Jana hopes other families will learn from her son's scare.
"You just think your kids are safe, they're inside your house, nothing's gonna go wrong, and I was surprised by the danger that was, just, what we were living with every day," she says.
If your home was built before the 1970's, it's likely it has non-safety glass.
Experts suggest you replace it or have it coated with a safety film.
If you are unsure, contact a glass specialist for help.
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