Core: Fuel symbols and the 1-minute rule

Since 2018 the same fuel symbols apply across all of Europe (Directive 2014/94/EU): you recognise petrol by the round symbol, diesel by the square symbol, and gas — including hydrogen — by the diamond-shaped symbol. You find them both on the pump and on the car's own filler flap. Did you tank the wrong fuel anyway? Do not start the engine. Once the engine runs, the wrong mixture can circulate through the lines and injectors. A separate, environment-focused piece of advice — not a legal duty: switch off the engine if you have to wait longer than about 1 minute, for example at a closed level crossing or in a queue that clearly lasts longer than a few seconds.