Sometimes the crash is survivable and the fire is not.
A second event
A person can, in principle, live through an impact the body was built to take. Then the fuel finds a spark, and a survivable wreck becomes a fatal one. The fire is not the same event as the collision. It is a second event, and often a preventable one.
How a car catches fire
The energy of a crash can rupture a fuel line or a tank and throw fuel into a fine mist. It does not take much to light it: a hot exhaust, a scrape of steel on pavement. Once lit, a fuel-fed fire builds fast and burns hot, in the seconds a stunned or trapped occupant does not have.
What fire does to the body
It is two injuries, not one. Burns over a large area of skin drive the body into shock as fluid pours out of the circulation. And the airway takes its own hit: breathing superheated gas and smoke injures the lungs from the inside, a harm that leaves no mark on the skin and sharply raises the odds of death.
The standard nobody sees
Federal rules require a car's fuel system to hold its fuel through a crash of defined severity, precisely so a survivable impact does not become a fire. When a vehicle burns after a wreck the body should have survived, the fuel system, its design and its condition, is the question.
The lesson
Separate the two events. Ask first whether the impact alone was survivable. If it was, the fire is a distinct harm, and a distinct question of responsibility. Claim only what the record and the science support, and that line holds.
On inhalation injury and burn mortality, see Does inhalation injury predict mortality in burns patients (PMC); on the federal fuel-system standard, 49 CFR 571.301, Fuel system integrity (FMVSS 301). This is general information, not medical or legal advice.
