Dangerous carbon monoxide alarms are being sold online, Which? has warned.
The consumer watchdog says devices that fail to detect high levels of the potentially lethal gas were found on eBay, Amazon, AliExpress and Wish.
Which? claims the government is failing to take “urgent action” to hold these marketplaces to account – and it first flagged one of the unsafe models to eBay seven years ago.
That device failed to respond to carbon monoxide in 10 out of 28 tests – and even when it did, the alarm was too quiet.
A total of 149 listings for dangerous carbon monoxide alarms were discovered across the four websites – and all of them have now been removed.
eBay was the only company to disclose sales figures, and revealed at least 1,311 had been sold on its platform.
Five dangerous alarm models – all unbranded and made in China – featured prominently on these websites when the “cheapest first” filter was chosen, with some being offered for as little as £5.
One alarm failed to trigger 22 times when carbon monoxide was in the air, while another product didn’t sound in 15 separate tests.
Sue Davies, the watchdog’s head of consumer protection policy, said: “Which? has been raising concerns about dangerous CO alarms for years, yet online marketplaces continue to allow them on their sites and into people’s homes, despite the potentially fatal consequences.
“This is the latest in a long line of examples of unsafe products being readily available on online marketplaces, with far too little action taken by the platforms to prevent them being allowed for sale.
“The government cannot delay any longer. It must move at pace to establish new regulations that put consumer safety first and enable tough enforcement action against online marketplaces that break the rules.”
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Avril and Gordon Samuel founded the Katie Haines Memorial Trust in 2010 following the death of their daughter from CO poisoning and have been campaigning for better awareness.
Avril said: “We have previously highlighted concerns about some carbon monoxide alarms being sold online, many coming from China, and campaigned vigorously about the need to purchase CO alarms only from reputable manufacturers and retailers.”
She added: “If the alarm is not to standard, this defence is negated and could have fatal results.”
Figures indicate that carbon monoxide poisoning has caused more than 200 accidental deaths in England and Wales in the last decade.
An Amazon spokesman said: “Safety is a top priority at Amazon. We require all products to comply with applicable laws and regulations and have developed industry-leading tools to prevent unsafe or non-compliant products from being listed in our stores.
“We have removed these products pending further investigation.”
An eBay spokesman said: “We take the safety of our users very seriously and immediately removed the listings reported to us by Which?
“We prohibit unbranded and unsafe brands of smoke or carbon monoxide detectors. We only allow sellers to list approved brands of carbon monoxide detectors and have taken action against the sellers who breached this policy.
“We continuously review and update the measures in place to prevent the sale of unsafe products. We have also conducted further sweeps of our site to remove any similar listings.”
A Department for Business and Trade spokesman said: “We take public safety extremely seriously which is why we are consulting on modernising our product safety framework to hold online marketplaces to account, ensuring items sold online meet the same standards as on the high street.
“If businesses don’t comply with product safety regulations, the Office for Product Safety and Standards will take appropriate enforcement action such as ordering the removal of the product from the market.”