Hello Shirker,
I must refere you to Damians second paragrapgh.
There is absolutely no doubt that CO is a very serious issue and the use of gas appliances should be carried out with a conscious regard for the potential dangers, BUT exactly the same must apply to the use of mains electrical devices and the risk of electric shock.
The construction standards that apply to gas and electrical appliances for touring caravans and motor homes seek to ensure the products are designed to be safe to use and present no practical danger to the caravanner. These include the products resistance to certain types of abuse. Specifically with regards to space heating in caravans gas appliances have to be room sealed, which ensures the gas and flue products are segregated from the living space.
The same overriding care has to be used when installing or using gas or electrical appliances, and that includes the important aspect of timely service/maintenance to keep the products working correctly.
I venture to suggest that bias against the use of a gas heater on the grounds of potential danger is unfounded, as electric heating also has potential dangers, all of which are controlled by proper design, correct installation and use, and timely maintenance.