Safety

Diesel fuel has low flammability, leading to a low risk of fire caused by fuel in a vehicle equipped with a diesel engine.

Yachts
In yachts diesels are used because petrol engines generate combustible vapors, which can accumulate in the bottom of the vessel, sometimes causing explosions. Therefore ventilation systems on petrol powered vessels are required.

Military vehicle safety
The United States Army and NATO use only diesel engines and turbines because of fire hazard. Diesel does not explode in a manner such as petrol does, it just slowly burns. US Army gasoline-engined tanks during World War II were nicknamed Ronsons, because it only took a single spark to ignite 50 or more gallons of highly volatile gasoline.