[Lucky Jim]

Incidentally there have been a spate of carbon monoxide deaths at Brit campsites because people brought their barbecues into the tent for the night, thinking they'd gone out, but they were still giving off fumes.
Also, CM detectors apparently don't always work in tents-

Shropshire campsite death: Girl, 14, killed in her tent by barbecue fumes | Mail Online

 

[Lucky Jim]

Probably brought 'em in to stop 'em getting pinched outside