THE VALUJET DC-9's cargo manifest reveals that up to 60 oxygen generators of a type used to supply passenger emergency oxygen masks in DC-10s and MD-80s were being carried as cargo to Atlanta, ValuJet's base. If charged, the generators can produce considerable heat when activated, scorching nearby material or fabric, and are classified as hazardous cargo.
These chemical oxygen-generating systems are typical of the devices used on MD-80s to provide emergency oxygen to passengers. Each canister contains sodium chlorate. The chemical-based emergency system was first introduced by Douglas Aircraft in the early 1970s on the DC-10 and is not used in the DC-9.
The FAA knows of three incidents when oxygen generators were inadvertently activated. Serious damage occurred in one, on 10 August, 1989, involving a parked American TransAir DC-10-40 which was destroyed by fire at Chicago.
Source: Flight International