By now, salesclerk Lexi Ney has it down to a science. Thirty seconds won't pass before a customer interested in buying one of this season's hottest gizmos asks the "blow-up" question.
"Are these the ones that blow up?" Alvin Budd, an IT professional from Conshohocken, asked Ney within seconds Sunday as he leaned in for a closer look at a LayZ Board hoverboard, ticketed at $549 at Status Shop, an urban clothing and sneaker store on South Street.
He was referring to reports of hovercraft batteries exploding and catching on fire. In November, for example, a house in Lafitte, La., was in flames within minutes of a battery exploding while being charged.
"It was like fireworks," Jessica Horne told reporters. She had purchased the battery-operated skateboard for her 12-year-old son.
Published reports point to problems with the device's lithium-ion batteries, the same type of battery found in many smartphones and laptops. But the batteries in hoverboards tend to be bigger.
The potential for problems led Overstock.com to halt hoverboard sales and offer refunds.
The U.S. Consumer Product Safety Commission said it is quickening its evaluation.
"The challenge is to move quickly but also thoroughly and carefully to find out why certain hoverboards caught fire," its chairman, Elliot F. Kaye, said in a statement last week.
Effective Dec. 11, Delta Airlines has banned hoverboards on its aircraft: "Manufacturers do not consistently provide detail about the size or power of their lithium-ion batteries."
The hoverboard's back-to-the-future character and its sheer-fun possibilities have made it "hugely popular," said toy expert Chris Byrne, content director for TTPM, a toy website.
"It's more of a sporting good than transport," he said. "It's good for entertainment and doing tricks, and it has a cool factor because there hasn't been anything like it.
"The problem is that there are no standards for them," he said. Some brands don't specify a weight limit, he said, so when heavier adults take them out for a spin, they may overheat the motor and cause batteries to ignite.
Toy Tips Research Institute founder Marianne Szymanski in Milwaukee said that when the toy began to get popular, parents bought low-priced, substandard brands and didn't carefully read instructions.
"Now we have a situation where the media has created the frenzy that every hoverboard is going to start on fire," she said. It's not likely to happen, she said, if the hoverboards are manufactured by well-known companies and if the parents choose brand-name batteries.
"Whatever hoverboard brand they get, they need to follow instructions," she said. "They can't rely on their kids."
At Status on Sunday, Ney sold one hoverboard, ticketed at $549, to a couple buying a present for their 13-year-old son. And, yes, they asked her if the LayZ Board brand at Status was one of those that blew up.
Ney said she told them what she tells every other customer: So far, Status hasn't heard any complaints. A Philadelphia Fire Department spokesperson said the same.
Budd told Ney he had heard about the blow-up issue but wasn't concerned, figuring fires happened in cheaper brands.
His main concern echoed an issue raised by the Consumer Product Safety Commission. "While the fire hazard has generated significant attention, I do not want to downplay the fall hazard," Kaye wrote.
That's why Budd, who is a big man, wouldn't put himself on a hoverboard. And the price tag kept him from buying.
But he's not as worried about his sons, 19 and 21, getting hurt.
"They fall off bikes," he said. "Taking a risk. That's what life's about. I'd rather they'd be out doing that than sitting on a sofa with phone."
Tips on how to buy and use hoverboards safely.
Buy from a reputable brick-and-mortar store or online retailer in case something goes wrong. Get a warranty.
Look for U.S. federal safety certifications.
Buy top-brand batteries.
Let device cool before charging.
Keep an eye on batteries while charging. Don't charge overnight. Most charge in two hours.
If the hoverboard gets hot, stop using it. Check with the manufacturer; it could be a faulty battery.
Wear helmets and pads to reduce injury from falls.