Gas fireplaces are popular because they eliminate the muss and fuss of wood-burning versions. But that convenience comes with a risk you may not be aware of: More than 80 percent of gas fireplaces sold last year have fixed glass panels that can become extremely hot—as hot as 1,328° F—because they don’t allow heat to escape. And the glass can remain dangerously hot for up to an hour after the gas is turned off. Touching the super-heated glass can instantly cause third-degree burns. Each year, those burns lead to about 17,000 medical visits, and up to 11 percent of the burns require surgery. Young children are especially at risk.

New gas fireplaces manufactured after January 1, 2015, must come with mesh safety screens that fit over the glass, according to mandatory industry standards developed with the Consumer Product Safety Commission. That’s a protective step we’ve been pushing for along with the American Academy of Pediatrics and others.

But the rule isn’t retroactive to the more than 10 million gas fireplaces in American homes, resorts, and other public places. If you have one in your home or business, it’s up to you to add a safety barrier. Despite the industry’s education efforts, some fireplace retailers may not know about the new rule. Contact the manufacturer; it might provide a barrier at no charge. Or you’ll have to buy one; they cost $100 to $900 or more depending on the size and style. Go to safefireplacetips.com for more information about what you need and where to get it. If you converted a wood-burning fireplace to gas and it has glass doors that you open when the gas is on, this warning doesn’t apply.