On the topic of car park fires,  the investigation into the Luton Airport car park fire has confirmed it was caused by a Diesel.
Fire at airport car park started accidentally | Bedfordshire Fire and Rescue Service
One of the lessons from the Liverpool car park fire, also started by a Petrol Range Rover, was the use of plastic fuel tanks in modern ICE’s is why fires spread so rapidly once they start.   
https://www.bafsa.org.uk/wp-content/...ark-Report.pdf
This combined with the high calorific value that modern cars means the fire risk is significantly higher today compared to when most multi storey car parks were built.
Eventually the calls for sprinkler protection to be mandated in all multi-storey car parks will be acted on.  Likewise you have to question if plastic fuel tanks should be banned as well.