AS winter sets in, cheap electric hand warmers have been selling well at street markets and on e-commerce platforms although many may be unsafe as they often fail to meet national standards, business insiders have warned.
The warmers use electricity to heat up a liquid inside.
Street markets on Henan Road S. and Sichuan Road N. sell the hand warmers for between 15 yuan (US$2.40) and 50 yuan each. Many of the cheap ones don't even list the manufacturer, Shanghai Daily has found.
On some e-commerce platforms, such cheap hand warmers are being sold with many vendors telling users to add water themselves to prevent leaks during transportation.
A worker with a hand warmer factory in Shenzhen told Shanghai Daily the government issued a national standard on heating devices in 2009.
It requires manufacturers to use a special material to separate the power source from the liquid. However, he said many unqualified hand warmer makers don't comply with this requirement to reduce costs. He said these products are unsafe because they can catch fire.
"Some manufactures use cloth or plastic to separate the power source from the heating liquid, which can be very dangerous as either can be easily damaged when the hand warmers are used frequently," he said.
The source added that there is a danger of such devices overheating and starting a fire when placed on a bed or sofa.
A worker surnamed Zhang, who works in the household electric appliance industry, told Shanghai Morning Post the national standard also requires manufacturers to install a pressure protection device in the hand warmers to prevent them from exploding.
Cheap products usually don't have such a device. If the power source malfunctions, the device will continue to heat the liquid until it becomes too hot, triggering an explosion, Zhang told the newspaper.
Last year, a Shanghai woman suffered serious burns on her left hand when her electric hand warmer exploded.
The warmers use electricity to heat up a liquid inside.
Street markets on Henan Road S. and Sichuan Road N. sell the hand warmers for between 15 yuan (US$2.40) and 50 yuan each. Many of the cheap ones don't even list the manufacturer, Shanghai Daily has found.
On some e-commerce platforms, such cheap hand warmers are being sold with many vendors telling users to add water themselves to prevent leaks during transportation.
A worker with a hand warmer factory in Shenzhen told Shanghai Daily the government issued a national standard on heating devices in 2009.
It requires manufacturers to use a special material to separate the power source from the liquid. However, he said many unqualified hand warmer makers don't comply with this requirement to reduce costs. He said these products are unsafe because they can catch fire.
"Some manufactures use cloth or plastic to separate the power source from the heating liquid, which can be very dangerous as either can be easily damaged when the hand warmers are used frequently," he said.
The source added that there is a danger of such devices overheating and starting a fire when placed on a bed or sofa.
A worker surnamed Zhang, who works in the household electric appliance industry, told Shanghai Morning Post the national standard also requires manufacturers to install a pressure protection device in the hand warmers to prevent them from exploding.
Cheap products usually don't have such a device. If the power source malfunctions, the device will continue to heat the liquid until it becomes too hot, triggering an explosion, Zhang told the newspaper.
Last year, a Shanghai woman suffered serious burns on her left hand when her electric hand warmer exploded.
