For an ESD to ignite fuel vapor, the vapor has to be between the upper and lower explosive limits. Gasoline is volatile enough that it rapidly exceeds the upper explosive limit in any kind of closed environment except in very cold conditions. In open environments, the vapor usually dissipates quickly enough to generally keep it below the lower explosive limit, except for very small areas. The guy was either very unlucky, or something else happened.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 401,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 26,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.
99 Mazda Miata 183,xxx miles.