The STF was set up by Thomas Cook as part of its response to the parents of Christi and Bobby Shepherd, who died from carbon monoxide poisoning while on a Cook holiday in 2006. The aim is to prevent further tragedies via the sharing of statistics on accidents and fatalities through an independent third party.

Among those that have signed up are Tui, Kuoni, Exodus, Neilson and Trek America. Katherine Atkinson, STF chief executive, told The Telegraph, which has campaigned on the issue, that others needed to follow the example.

“We need more companies to follow suit as soon as possible so that we can build up an accurate picture of what goes wrong for British families on holiday, based on solid evidence,” she said.

She added: “Wouldn’t it be great if we were able to give families a better understanding of where the real risks are before they go away this summer?”

The STF also has the backing of some online brands, including Expedia. It is hoped to attract more of these, particularly websites that deal with direct property lets, which often do not check the accommodation being let out.

As well as advice on carbon monoxide, the STF website also has tips for different traveller groups, including disabled, LGBT and older travellers.