I know everyone already knows this, but it doesn't heard to be reminded.

Please be Very Careful when using propane appliances for space heating in
any enclosed space, especially in a small RV. We often see folks posting
heater ideas on this and other forums, and it�s so important to remember
that safety must be paramount. I read in the paper today that tragically,
three people have died in this cold snap because they were using improperly
vented propane appliances. One couple died of CO poison in a school bus,
another guy died in a camper. So whenever you are contemplating burning
propane for heat, or installing a propane appliance, be very, very careful.
It�s very important that all applicable codes are learned and followed when
doing an installation. I remember once installing a propane fridge replacing
the old two way, and it seemed I had to cut off half the side of the van to
provide the ventilation called for.

Nathaniel