What You Must Never Burn Indoors (And Why People Still Do)
Charcoal, generators, camping stoves and patio heaters kill people indoors every winter. The mechanism behind each, and what to use instead.
Carbon monoxide, alarms, ventilation math and the failure modes that turn a working heater into a hazard.
This is the section everything else on the site depends on. Carbon monoxide is produced whenever a carbon-based fuel burns without enough oxygen, it is colourless, odourless and tasteless, and it binds to haemoglobin roughly 200 to 250 times more strongly than oxygen does. Its early symptoms — headache, nausea, dizziness, confusion — read as flu, and the confusion arrives before the alarm does.
Two facts here surprise most readers. The first is that a fully compliant CO alarm is deliberately slow: under UL 2034 it must not sound below 30 ppm within 30 days, and may take up to four hours at 70 ppm. That is by design, to avoid nuisance alarms, and it means silence is not evidence of clean air. The second is that the most dangerous objects are not heaters at all — charcoal, generators and camping stoves brought indoors during a power cut cause a predictable cluster of deaths after every major storm.
If you read one thing before lighting anything indoors, read the guides in this section.
Charcoal, generators, camping stoves and patio heaters kill people indoors every winter. The mechanism behind each, and what to use instead.
Where to mount a CO alarm, which standard to buy, what the ppm numbers mean, and why a compliant alarm can stay silent at harmful levels.