In the early 2000s Takata started using phase-stabilized ammonium nitrate (PSAN) as an airbag propellant. Itās cheap and plentiful, but when itās exposed to moisture the āphase stabilizedā part breaks down and it develops a crystal phase transition at 90F/32C. Thatās a temperature that parked cars reach frequently, and the propellant wafers expand and crack.
The cracks in the propellant increase its surface area and make it burn faster and more violently, rupturing the steel canister inside the airbag assembly and sending shrapnel toward the driver when the airbag detonates.
After reports of ruptures mounted in the mid-2000s, Takata started to add a desiccant inside the inflator to keep the propellant dry and slow the cracking process.
However, not all of Takataās output included that desiccant, and this is a remarkably late example of a non-desiccated airbagāa design that Takata knew was unsafe for a decade before this was manufactured in 2014.