Carbon Monoxide can kill without warning. In a survival situation, you may be using open flames or burning charcoal in fairly enclosed spaces, which can be deadly. A Carbon Monoxide detector with a longlife battery would be really useful to prevent tragedy.
Good thought/s, but I have other plans in place which call for using a wood stove for heat & cooking, & having it vented properly. This is preplanning & don’t forget to get the flue checked & cleaned regularly [at least once a year for low use years & more frequently for years of a lot of use]
We buy every stick type candle we see a garage sales etc. EMP no problem.