Deaths from carbon monoxide (CO) poisoning have trebled in the last year, according to a report.
In the 12-month period to June 30, there were 50 recorded incidents involving CO poisoning in the UK, the Gas Safety Trust said.
Of the 105 people involved, there were 25 fatalities and 80 injuries without fatal consequences - more than three times as many as the seven deaths reported in 2010, the Trust said.
The Carbon Monoxide Hotspot Report 2011, which contains figures of incidents gained from media reports, says the high number of fatalities can be explained by the occurrence of several serious incidents in the past 12 months.
Northern Ireland suffered particularly badly, with two incidents in Co Londonderry and Co Fermanagh claiming two and three lives respectively.
The number of people involved in incidents fell from 145 the previous year.
The top hotspot for CO related incidents, when population is taken into account, was Devon, followed by Somerset, Staffordshire, Northern Ireland, Cheshire and Essex.
As is usually the case, the highest numbers of incidents were experienced between November and February (58% of total incidents). However, there were also cases in the summer when camping equipment and fires are used more.
The Trust warned that the real figures could actually be much higher.
Nigel Dumbrell, head of charitable operations, said: "While deaths and serious injuries from CO exposure are relatively straightforward to record, the data does not reveal the extent of what might be termed 'near misses'. The records do not capture information about the number of people who are unwittingly exposed to low levels of CO poisoning; levels that may cause long-term ill health but go undetected."